Blood test apparatus and method of controlling the same

ABSTRACT

A blood test apparatus having a simple constitution whereby stable measurement can be conducted by surely sampling the blood in an amount being small but sufficient for the test without placing too much burden on a patient. 
     When a first skin contact sensor of this apparatus detects the skin, driving of a negative pressure unit is initiated (time point  166   a ). Thus, the skin rises and comes into contact with a second skin contact sensor (time point  166   b ). After piercing into the skin at time point  166   c,  the negative pressure supply is once ceased. Next, the negative pressure is applied again at time point  166   d  for a definite period of time. Thus, the opening in the skin is broadened, which facilitates the flow out of the blood ( 16 ).

TECHNICAL FIELD

The present invention relates to a blood test apparatus and its controlmethod used to examine blood components, for example.

BACKGROUND ART

Diabetes patients need to measure the blood sugar level regularly andadminister insulin based on the blood sugar level to maintain a normalblood sugar level. To maintain this normal blood sugar level, diabetespatients need to measure the blood sugar level regularly, sample a smallamount of blood from fingertips using a blood test apparatus, andmeasure the blood sugar level from this sampled blood.

The conventional blood test apparatus generally uses a needle as a meansfor puncturing skin (see Patent Document 1, for example). As shown inFIG. 1, conventional blood test apparatus 1 which uses a needle as apuncturing means, includes: housing 2 that forms a chassis; cylindricalbody 3 that is provided at which one side of housing 2 opens; plunger 4that moves back and forth inside cylindrical body 3; handle 5, one endof which is connected to plunger 4; latch part 6 that latches handle 5at housing 2; spring 7 that urges handle 5 toward opening part 3 a ofcylindrical body 3; lancet 9 which has one end held by plunger 4 and theother end attached with blood collection needle (hereinafter “needle”)8; holding part 11 that holds blood sensor 10 on the side of openingpart 3 a; and electrical circuit section 12 to which output of bloodsensor 10 is connected.

To examine blood using conventional blood test apparatus 1, thefollowing preparation works are necessary. Blood sensor 10 and needle 8are replaced to eliminate the influence of blood which has alreadyexamined. To remove blood sensor 10 after use and attach new bloodsensor 10, holding part 11 is removed and then blood sensor 10 after useis removed. Next, new blood sensor 10 is attached to holding part 11.Then, holding part 11 is attached to opening part 3 a again. If theneighborhood of holding part 11 is stained with, for example, blood, itis cleaned.

These preparation works are troublesome for diabetes patients with pooreyesight. In addition, these works must be performed several times a dayand are burdensome.

After these preparation works are done, blood test apparatus 1 isabutted on the skin of the patient, and the latching of latching part 6is released. Then, handle 5, urged by spring 7, is propelled in thedirection of arrow 14. By this release of latching of handle 5, needle8, connected to this handle 5 via plunger 4 and lancet 9, is alsopropelled at the same time. Needle 8 breaks through blood sensor 10 andpunctures skin 13.

A small amount of blood 16 flows out from punctured skin 13. The outflowof blood 16 is guided inside blood sensor 10. Blood 16 guided into bloodsensor 10 causes chemical changes in blood sensor 10 according to theblood sugar level of the patient. The current produced by the chemicalchanges is led to electrical circuit section 12, and the blood sugarlevel is measured. The calculated blood sugar level is displayed ondisplay section 15. Based on the calculated blood sugar level, forexample, basic data showing the amount of insulin to administer to thepatient is provided.

On the other hand, an apparatus for sampling blood using laser light forthe puncturing means, is also proposed (see Patent Document 2 and PatentDocument 3). Use of laser light provides an advantage of makingunnecessary replacement of needle possibly alleviating the pain of thepatient upon puncturing. Particularly, Patent Document 2 discloses anapparatus for sampling blood using laser light as a puncturing means andthat improves the circulation of blood by sucking in the skin area to bepunctured.

-   Patent Document 1: Japanese Patent Application Publication No.    2003-524496-   Patent Document 2: Japanese Patent Application Publication No.    2004-533866-   Patent Document 3: Japanese Patent Application Laid-Open No.    2004-195245

DISCLOSURE OF INVENTION Problems to be Solved by the Invention

However, an effect of stimulating a flow of blood in the punctured areacannot be obtained enough by only sucking in the skin area to bepunctured, and there is a case where a desired amount of blood cannot beobtained.

Further, when suction is assumed in the actual applied situation, thefollowing disadvantages become concerns. For example, assuming that skinis sucked using a negative pressure means such as a pump, when bloodcollection is detected and the negative pressure means stops operating,the patient moves the blood test apparatus or the finger when theoperation noise of the negative pressure stops, which may make itimpossible to perform measurement after blood collection in a stablemanner. Further, when the negative pressure means is made to operate tocollect blood, the conditions of skin such as hardness vary betweenpatients, and so the amount of blood collected may become excessive orinsufficient depending on the effect (a certain sucking force) of thenegative pressure means. If the sucking force is made too large, bloodis oversampled and a load is placed on the patient, and, if the suckingforce is made too small, it is difficult to collect a small amount ofblood required and enough for measurement.

In short, when the actual applied situation is assumed, if suction iscontrolled only on and off, a small amount of blood required and enoughfor measurement cannot be collected, and stable measurement cannot beperformed without placing a load on the patient. Although it isnecessary to perform control more precisely to realize this, researchesand developments from this viewpoint have not been undertakenconventionally.

It is therefore an object of the present invention to provide a bloodtest apparatus and its control method that can collect a small amount ofblood required and enough for measurement in a reliable manner andperform stable measurement without placing a load on the patient with asimple configuration.

Means for Solving the Problem

The blood test apparatus of the present invention punctures skin using alaser to collect and measure blood and includes: a laser puncturingsection that emits a laser light to puncture the skin; a blood sensorthat collects and analyzes the blood flowing out from the puncturedskin; a holder that holds the blood sensor; a negative pressure sectionthat creates a negative pressure in a space near the blood sensor; and anegative pressure controlling section that controls an operation of thenegative pressure section, and in the blood test apparatus, the negativepressure controlling section changes a level of the negative pressure inthe space near the blood sensor using a predetermined pattern, in atleast part of a period from when the skin abuts on the holder until whenthe measurement is complete.

The blood test apparatus of the present invention punctures skin using alaser and collects and measures blood, and includes: a laser puncturingsection that emits a laser light to puncture the skin; a blood sensorthat collects and analyzes the blood flowing out from the puncturedskin; a holder that holds the blood sensor; and a negative pressuresection that creates a negative pressure in a space near the bloodsensor, and in the blood test apparatus, the negative pressure sectiondrives a manual pump to create the negative pressure.

The controlling method of the present invention is for a blood testapparatus that includes: a laser puncturing section that emits a laserlight to puncture skin; a blood sensor that collects and analyzes bloodflowing out from the punctured skin; a holder that holds the bloodsensor; a negative pressure sect ion that creates a negative pressure ina space near the blood sensor; and a negative pressure controllingsection that controls an operation of the negative pressure section, andin the controlling method, in at least part of a period from when theskin abuts on the holder until when measurement is completed, a level ofthe negative pressure in the space near the blood sensor is changedusing a predetermined pattern.

Advantageous Effect of the Invention

According to the present invention, it is possible to collect a smallamount of blood required and enough for measurement and perform stablemeasurement without placing a load on the patient with a simpleconfiguration.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view showing an example of the conventionalblood test apparatus;

FIG. 2 is an exploded assembly perspective view showing a first exampleof a blood test apparatus of the present invention;

FIG. 3 is an exploded assembly perspective view showing a second exampleof the blood test apparatus of the present invention;

FIG. 4 is a side view of the blood test apparatus of FIG. 3;

FIG. 5 is an exterior perspective view showing an example of a laseremitting apparatus in the blood test apparatus of the present invention;

FIG. 6A is a cross-sectional view showing a configuration example of thelaser emitting apparatus of FIG. 5;

FIG. 6B is a cross-sectional view showing another configuration exampleof the laser emitting apparatus of FIG. 5;

FIG. 7 is a partially broken perspective view showing another example ofthe laser emitting apparatus in the blood test apparatus of the presentinvention;

FIG. 8 is a cross-sectional view showing an example of a blood sensor inthe blood test apparatus of the present invention;

FIG. 9 is a cross-sectional view showing another example of the bloodsensor in the blood test apparatus of the present invention;

FIG. 10 is a cross-sectional view of the blood sensor of FIG. 9 uponpuncturing;

FIG. 11 is a cross-sectional view showing still another example of theblood sensor in the blood test apparatus of the present invention;

FIG. 12 is a transparent plan view of the blood sensor of FIG. 8;

FIG. 13 is a transparent plan view showing still another example of theblood sensor in the blood test apparatus of the present invention;

FIG. 14 is a transparent plan view showing still another example of theblood sensor in the blood test apparatus of the present invention;

FIG. 15 shows exploded plan views of the blood sensor of FIG. 8, whereFIG. 15A shows a plan view of the cover, FIG. 15B shows a plan view ofthe spacer, and FIG. 15C shows a plan view of the substrate;

FIG. 16 is a cross-sectional view showing a blood sensor unit and itsneighborhood in the blood test apparatus of the present invention;

FIG. 17 is an exploded elevation view showing the primary part of aguide part for attaching the blood sensor unit to the blood testapparatus of the present invention;

FIG. 18 is a perspective view showing an example of the blood sensorunit in the blood test apparatus of the present invention;

FIG. 19 is a cross-sectional view of the primary part of oneconfiguration example showing the neighborhood of the lower end of aholder in the blood sensor unit of FIG. 18;

FIG. 20 is a cross-sectional view of the primary part of anotherconfiguration example showing the neighborhood of the lower end of theblood sensor unit in the blood test apparatus of the present invention;

FIG. 21 is a cross-sectional view of the primary part of still anotherexample showing the neighborhood of the lower end of the blood sensorunit in the blood test apparatus of the present invention;

FIG. 22 is a cross-sectional view of the blood sensor unit of FIG. 18;

FIG. 23 is a cross-sectional view showing another example of the bloodsensor unit in the blood test apparatus of the present invention;

FIG. 24 is a cross-sectional view showing still another example of theblood sensor unit in the blood test apparatus of the present invention;

FIG. 25 is a plan view showing the blood sensor unit of FIG. 24;

FIG. 26 is a graph showing the relationship between the distance fromthe focal point of laser light to the puncturing target (X axis) and theburn pattern diameter (Y axis), in the blood test apparatus of thepresent invention;

FIG. 27 is an enlarged cross-sectional view of the primary part showingan example of a negative pressure chamber and a negative pressure pathin the blood test apparatus of the present invention;

FIG. 28 is an enlarged cross-sectional view of the primary part showinganother example of the negative pressure chamber and the negativepressure path in the blood test apparatus of the present invention;

FIG. 29 illustrates the volume of the negative pressure chamber shown inFIG. 27;

FIG. 30 illustrates the volume of the negative pressure chamber shown inFIG. 28;

FIG. 31 is a block diagram showing an electrical circuit section in theblood test apparatus of the present invention;

FIG. 32 is a flowchart showing an example of steps of a test using theblood test apparatus of the present invention; FIG. 33A is across-sectional view showing individual steps in an example of steps ofa test using the blood test apparatus of the present invention morespecifically;

FIG. 33B is a cross-sectional view showing individual steps followingFIG. 33A;

FIG. 33C is a cross-sectional view showing individual steps followingFIG. 33B;

FIG. 33D is a cross-sectional view showing individual steps followingFIG. 33C;

FIG. 34 is a flowchart showing another example of steps of a test usingthe blood test apparatus of the present invention;

FIG. 35 illustrates an example of negative pressure control in the bloodtest apparatus of the present invention;

FIG. 36 schematically shows how skin is lifted by the negative pressurecontrol illustrated in FIG. 35;

FIG. 37 illustrates another example of the negative pressure control inthe blood test apparatus of the present invention;

FIG. 38 is an exploded assembly perspective view showing an example ofthe laser perforation apparatus included in the blood test apparatus ofthe present invention;

FIG. 39 shows an example of laser branch control in the blood testapparatus of the present invention;

FIG. 40 illustrates the laser branch control of FIG. 39;

FIG. 41 is a perspective view of a cubic optical device that can be usedin the laser branch control of FIG. 39;

FIG. 42 shows examples of a cube that can be used in the laser branchcontrol in FIG. 39, where FIG. 42A shows branch of the laser light usinga three-dimensional image, and FIG. 42B shows an example of a cube thatrealizes the branch;

FIG. 43 shows how a laser light is emitted from an oblique direction andpunctures skin with the blood test apparatus of the present invention;

FIG. 44 shows variations in the shape of emission of the laser light;

FIG. 45 is a schematic view showing another example of laser outputcontrol in the blood test apparatus of the present invention;

FIG. 46 shows an example of laser pulse control in the blood testapparatus of the present invention;

FIG. 47 is a cross-sectional view showing a puncturing state by thelaser pulse control in FIG. 46;

FIG. 48 shows still another examples of the laser output control in theblood test apparatus of the present invention, where FIG. 48A shows acircuit diagram, FIG. 48B shows a time fluctuation of the currentinputted to a flashlamp, and FIG. 48C shows a time fluctuation of alaser output;

FIG. 49 shows still another examples of the laser output control in theblood test apparatus of the present invention, where FIG. 49A shows acircuit diagram, FIG. 49B shows a time fluctuation of the currentinputted to the flashlamp, and FIG. 49C shows a time fluctuation of thelaser output;

FIG. 50 is a block diagram showing a first example of a power supplycontrolling section of the blood test apparatus of the presentinvention;

FIG. 51 is a flowchart showing a first example of control steps of thepower supply controlling section of FIG. 50;

FIG. 52 is a flowchart showing a second example of the control steps ofthe power supply controlling section of FIG. 50;

FIG. 53 is a flowchart showing a third example of the control steps ofthe power supply controlling section of FIG. 50;

FIG. 54 is a flowchart showing a fourth example of the control steps ofthe power supply controlling section of FIG. 50;

FIG. 55 is a block diagram showing a second example of the power supplycontrolling section of the blood test apparatus of the presentinvention;

FIG. 56 is a flowchart showing a first example of control steps of thepower supply controlling section of FIG. 55;

FIG. 57 is a flowchart showing a second example of the control steps ofthe power supply controlling section of FIG. 55;

FIG. 58 is a block diagram showing a third example of the power supplycontrolling section of the blood test apparatus of the presentinvention;

FIG. 59 is a flowchart showing a first example of control steps of thepower supply controlling section of FIG. 58;

FIG. 60 is a flowchart showing a second example of the control steps ofthe power supply controlling section of FIG. 58;

FIG. 61A is a graph illustrating a method of setting a charge level forcharging the laser emitting apparatus stepwise based on the batterylevel;

FIG. 61B is a graph illustrating a method of setting the charge levelfor charging the laser emitting apparatus continuously based on thebattery level;

FIG. 61C is a graph illustrating a method of setting a charge level forcharging the laser emitting apparatus according to a variable curvebased on the battery level;

FIG. 62 is a graph showing the relationship between the battery voltage(Y axis) and the battery level (X axis) when the charge level ischanged;

FIG. 63 shows another examples of the laser branch control in the bloodtest apparatus of the present invention, where FIG. 63A shows a casewhere a laser light is divided into two branches, and FIG. 63B shows acase where a laser light is divided into four branches;

FIG. 64 is a schematic view showing the configuration of an opticalfiber directional coupler used in the laser branch control of FIG. 63;and

FIG. 65 shows still another example of the laser branch control in theblood test apparatus of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The blood test apparatus of the present invention will be describedbelow with reference to the drawings. Common parts in the figures willbe assigned the same reference numerals without further explanations.

Overall View 1 of the Apparatus

FIG. 2 is an exploded assembly perspective view showing a first exampleof the overall configuration of the blood test apparatus including thelaser perforation apparatus of the present invention.

The interior of lower case 32 of blood test apparatus 31 shown in FIG. 2accommodates components including: laser emitting apparatus 33; negativepressure means 34 which is configured with suction pump (negativepressure pump) 34 a, pump valve unit 34 b and vent switch 34 c; battery35 which supplies power to electrical components; electrical circuitsection 36 which is mounted on these components; and display section 37which is mounted on electrical circuit section 36, and, for example,made of liquid crystal.

Apparatus body 39 is configured so that upper case 38 covers lower case32 that accommodates the components. Transparent display window 38 a isprovided in upper case 38 in the position corresponding to displaysection 37.

Apparatus body 39 is connected to blood sensor unit 44 via adapter 40.One end of adapter 40 is a cylinder shaped body, and blood sensor unit44 is inserted removably into adapter 40. Blood sensor unit 44 isconfigured with holder 41 and blood sensor 42 attached inside holder 41.Window 43 provided in the center of blood sensor unit 44 is a part forallowing laser light from the laser emitting port of laser emittingapparatus 33 to pass through. Window 43 may be a throughhole or a memberformed with a material that allows laser light to pass through.

Overall view 2 of the apparatus FIG. 3 is an exploded assemblyperspective view showing a second example of the overall view of theblood test apparatus of the present invention. FIG. 4 is its side view.Blood test apparatus 31 a shown in FIG. 3 and FIG. 4 is different fromblood test apparatus 31 shown in FIG. 2 in that the apparatus has amanual pump that can perform suction manually as a negative pressurepump constituting negative pressure means 140. The difference will bedescribed below.

Blood test apparatus 31 a has negative pressure means 140 includingmanual pump (negative pressure pump) 141 and manual pump knob 142 thatdrives manual pump 141 manually. Vent switch 144 releases the negativepressure created in pump valve unit 143 to the atmosphere.

Manual pump knob 142 has the shape of an arch, and its one end is madespindle 142 a and the other end is made operating part 142 b (see FIG.4). Manual pump knob 142 can rotate around spindle 142 a. Operating part142 b transmits power to manual pump 141. The patient holds manual pumpknob 142 with apparatus body 39 and can move operating part 142 b up anddown. Manual pump 141 operates in this up-and-down motion, and anegative pressure is created.

To create an adequate negative pressure by the up-and-down motion ofoperating part 142 b while checking a lift of the skin, the exterior ofblood sensor unit 44 is preferably formed with a transparent material sothat the interior of negative pressure chamber 60 (see FIG. 16, forexample) can be seen. The overall exterior of blood sensor unit 44 maybe formed with a transparent material or only the tip 41 h side (thenegative pressure chamber 60 side) of blood sensor unit 44 may be formedwith a transparent material. Grip part 142 c of manual pump knob 142 mayhave finger-shaped pattern with indentations and projections to preventthe fingers from slipping.

By driving negative pressure means 140 manually, it is not necessary tosupply power for driving negative pressure means 140, which extends thelife of battery 35 and makes the apparatus suitable for a portable bloodtest apparatus.

The First Aspect of the Laser emitting Apparatus (Including a Lens)

Blood test apparatuses 31 and 31 a of the present invention use laserlight as a means for puncturing skin. When the skin is irradiated withlaser light, the laser light is absorbed in the OH group of water ofskin, heat increases instantaneously and the water evaporates. Thesurrounding cells also evaporate at this time, thereby opening a hole inthe skin.

Blood test apparatuses 31 and 31 a accommodate laser emitting apparatus33. FIG. 5 is an exterior perspective view of laser emitting apparatus33 accommodated in blood test apparatuses 31 and 31 a. Further, FIG. 6Aand FIG. 6B are cross-sectional views of laser emitting apparatus 33. InFIG. 6A, laser crystal 33 d is arranged in the internal part surroundedby walls where partially reflecting mirror 33 f and total reflectionmirror 33 g are provided. In FIG. 6B, laser crystal 33 d has partiallyreflecting mirror 33 f and total reflection mirror 33 g on both sidesand is attached on the outer wall and the inner wall (partition) ofcylindrical body 33 b. That is, in FIG. 6B, laser crystal (laser rod) 33d is long and extends beyond the inner wall (partition).

Laser emitting apparatus 33 is configured with oscillation tube 33 a andcylindrical body 33 b connected to front side of oscillation tube 33 a.Laser emitting port 33 c is provided in the center of the front side ofcylindrical body 33 b.

Oscillation tube 33 a accommodates inside Er:YAG (yttrium aluminumgarnet) doped with erbium, or Ho:YAG laser crystal 33 d doped withHolmium, and excitation light source 33 e which includes a xenonflashlamp. Partially reflecting mirror 33 f is attached in one end ofoscillation tube 33 a (particularly, see FIG. 6A). The transmittance ofpartially reflecting mirror 33 f may be approximately to 10%. Totalreflection mirror 33 g with the transmittance of 99 to 100% is attachedto the other end of oscillation tube 33 a (see FIG. 6A and FIG. 6B).Further, instead of using partially reflecting mirror 33 f and totalreflection mirror 33 g, films having the same properties may be formedon the end face of laser crystal 33 d by sputtering.

Convex lens (focus lens) 33 h is mounted inside cylindrical body 33 b.Convex lens 33 h focuses laser light near the surface of blood sensor 42(described in detail later). Total reflection mirror 33 g, YAG lasercrystal 33 d, partially reflecting mirror 33 f, lens 33 h and laseremitting port 33 c are arranged in this order.

The process of emitting laser light from laser emitting apparatus 33will be described. For example, the excitation light emitted fromexcitation light source 33 e penetrates to Er:YAG laser crystal 33 d andcreates a high energy state by exciting Er (erbium) ion. By this means,Er:YAG laser crystal 33 d enters a reverse distribution state, and laserlight resonates and is amplified by passing through YAG laser crystal 33d while reflecting between total reflection mirror 33 g and partiallyreflecting mirror 33 f. The same applies to the case of Ho (Holmium).Part of the amplified laser light passes through partially reflectingmirror 33 f by stimulated emission. The laser light passing throughpartially reflecting mirror 33 f passes through lens 33 h and is emittedfrom laser emitting port 33 c. As described later, the laser lightemitted from laser emitting port 33 c punctures (illuminates) the skin.

The Second Aspect of the Laser Emitting Apparatus

FIG. 7 shows another example of the laser emitting apparatus. Laseremitting apparatus 189 shown in FIG. 7 irradiates two kinds of lasercrystals with excitation light using one flashlamp 185 as an excitationlight source. At this time, laser lights are outputted from therespective laser crystals. Use of two types of crystals enables outputof laser lights of different intensities or wavelengths.

As shown in FIG. 7, laser emitting apparatus 189 includes: chassis 188which has a shape of two overlapping cylindrical bodies having anelliptical cross section; flashlamp 185 for exciting laser light, whichis arranged in the center part of chassis 188; and first crystal 186 andsecond crystal 187 for oscillating laser light, which are arranged atthe both sides of flashlamp 185. There are three focuses in ellipticalchassis 188. Chassis 188 has a shape of two overlapping ellipses. Eachellipse has two focuses and shares one focus with the other ellipse, sothat there are three focuses. Out of the three focuses, first crystal186 is arranged in one of the focuses, and second crystal 187 isarranged in another focus. Flashlamp 185 is arranged in the center partwhere two focuses overlap. One flashlamp 185 can generate laser lightsfrom two crystals 186 and 187, so that it is possible to realize asmaller and lower-cost laser emitting apparatus.

The output intensity of the laser light is proportional to the lightemitting intensity of the flashlamp 185 and is also proportional to thevolumes of crystal 186 and crystal 187. Therefore, by arranging twocrystals of the same diameter and different lengths, it is possible toobtain two laser lights of different intensities using one flashlamp185.

Further, by using crystals of the same volume, it is possible to outputtwo laser lights of the same intensity at a time. Therefore, even if alaser light is not divided into branches (see FIG. 40 and FIG. 41), skincan be punctured with two laser lights of the same intensity. In thiscase, energy loss due to branching by a splitter and mirror isprevented.

By arranging two crystals of different compositions (for example, anEr:YAG laser crystal with a wavelength of 2.94 μm and an Nd:YAG crystalwith a wavelength of 1.06 μm), it is possible to obtain laser lightshaving different wavelengths. By irradiating the same position withlaser lights having different wavelengths, it is possible to make pricksof different depths in skin. For example, the absorption rate of the OHgroup varies between Er:YAG and Nd:YAG. Therefore, it is possible tomake a shallower prick using Er:YAG having a high absorption rate andmake a deeper prick using Nd:YAG having a lower absorption rate thanEr:YAG. By emitting two laser lights at the same time utilizing theseproperties, it is possible to make a prick on the skin more efficiently.When the two laser lights are emitted, Er:YAG and Nd:YAG are preferablyemitted in this order with a little time lag.

By using laser emitting apparatus 189, it is possible to select thewavelength of the laser light to be used. Further, by irradiating thesame position with two kinds of laser lights using an optical system, itis possible to improve output intensity.

Blood test apparatuses 31 and 31 a of the present invention use laseremitting apparatuses 33 and 189 that can perform puncturing withoutcontacting the skin, as a means for puncturing the skin of the patient,so that a puncturing needle required in the conventional blood testapparatus is not required. Further, blood test apparatuses 31 and 31 ause a puncturing means that does not contact the skin of the patient,and so are sanitary. Still further, although it is necessary to replacethe puncturing needle every test in the conventional blood testapparatus, the test by blood test apparatuses 31 and 31 a of the presentinvention does not require this replacement.

Further, blood test apparatuses 31 and 31 a of the present invention donot require moving components for moving a needle required forpuncturing with a needle, which reduces troubles. Further, the number ofcomponents required in blood test apparatuses 31 and 31 a of the presentinvention is reduced, so that components control becomes simple.Further, by providing a transparent waterproof wall on the front face oflaser emitting port 33 c, it is possible to wash the whole of blood testapparatuses 31 and 31 a.

The Blood Sensor

Blood test apparatuses 31 and 31 a of the present invention have a bloodsensor taking in blood flowing out from the punctured skin and examiningthe blood components.

The First Example of the Blood Sensor

FIG. 8 is a cross-sectional view of a first example of the blood sensor.Blood sensor 42 shown in FIG. 8 has an outer shape of a round orpolygon. Base plate 45 constituting blood sensor 42 has: substrate 46;spacer 47 stacked on the upper face of substrate 46; and cover 48stacked on the upper face of spacer 47.

Blood storing part 49 is provided near the center of base plate 45.Storing part 49 is formed to communicate with hole 46 a provided insubstrate 46 and hole 47 a provided in spacer 47. Storing part 49 opensdownward to collect blood from the skin. The volume of storing part 49is, for example, 0.904 μL, but is by no means particularly limited. Oneend of supply channel 50 is connected to storing part 49. The volume ofsupply channel 50 is, for example, 0.144 μL, but is by no meansparticularly limited. Detecting section 51 is arranged inside supplychannel 50.

Blood stored in storing part 49 flows into supply channel 50 bycapillary action and is led to detecting section 51. The other end ofsupply channel 50 is connected to air hole 52. The diameter of air hole52 may be approximately 50 μm to 250 μm. By making the diameter of airhole 52 small, blood is prevented from overflowing from air hole 52.Further, in a state where storing part 49 is in close contact with theskin, air hole 52 operates as a negative pressure path that creates anegative pressure in storing part 49.

Reagent 53 mounted on detecting section 51 may be prepared asappropriate according to a test target. For example, reagent 53 isprepared by dropping on detecting section 51 arranged on substrate 46 areagent solution prepared by adding and dissolving an enzyme (PQQ-GDH)of 0.1 to 5.0 U/sensor, potassium ferricyanide (10 to 200 mM), maltitol(1 to 50 mM) and taurine (20 to 200 mM) to a 0.01 to 2.0 wt % aqueoussolution of CMC, and drying the reagent solution.

Storing part 49 of blood sensor 42 is sealed with face 49 a(hereinafter, referred to as a “ceiling face”).

The emitted laser light preferably transmits through ceiling face 49 a,because blood flowing out from the skin punctured with laser light doesnot flow out from ceiling face 49 a. To allow the laser light totransmit through ceiling face 49 a, cover 48 may be formed with thematerial that allows laser light to transmit (for example, glass,plastic such as polyimide or resin material).

Further, if the emitted laser light cannot transmit through ceiling face49 a, the laser light may perforate ceiling face 49 a. If the laserlight perforates ceiling face 49 a, substrate 46, spacer 47 and cover 48may be formed with the same material.

The hole formed in ceiling face 49 a can serve as air hole 52, as wellas a negative pressure path through which the negative pressure meanscreates a negative pressure in storing part 49.

The Second Example of the Blood Sensor

FIG. 9 is a cross-sectional view of the second example of the bloodsensor. While ceiling face 49 a of storing part 49 of blood sensor 42shown in FIG. 8 is sealed, the ceiling face of storing part 49 of bloodsensor 103 shown in FIG. 9 is open.

Hole 103 b is formed in cover 48 of blood sensor 103. Preferably, thediameter of hole 103 b (for example, 1.0 mm) is smaller than thediameter of storing part 49 (for example, 2.0 mm), and is greater thanthe diameter of air hole 52 (50 μm to 250 μm). Hole 103 b is preferablylocated in the center of the ceiling face of storing part 49. Laserlight passes through hole 103 b and punctures the skin. By providinghole 103 b, it is possible to prevent laser light from declining. It isthereby possible to save energy of laser light to be emitted.

Hole 103 b can serve as air hole 52 as well as a negative pressure paththrough which negative pressure means 34 and 140 create a negativepressure in storing part 49.

As shown in FIG. 10, the surface tension of blood 16 generated insidehole 103 b prevents blood 16 collected by puncturing the skin fromoverflowing out from the upper face of the cover. Blood 16 spreadsinside storing part 49. Therefore, it is possible to collect an adequateamount of blood 16. Blood 16 that fills storing part 49 flows intosupply channel 50 by capillary action.

If hole 103 b is water-repellent, blood 16 is less likely to overflowthrough hole 103 b. Therefore, the interior of blood test apparatuses 31and 31 a is not contaminated with blood.

Polyethylene terephthalate (PET) can be used as the material of cover 48of blood sensor 103, and the same material as substrate 46 and spacer 47can be used. Therefore, material control is simple.

Laser light passes through hole 103 b of storing part 49. Laser lightmay pass through the center of hole 103 b or pass through a position offthe center of hole 103 b. For example, by making laser light passthrough a farther position from supply channel 50 across the center ofhole 103 b, blood 16 flowing out from skin 13 fills the interior ofstoring part 49 completely, and then flows into supply channel 50, sothat it is possible to realize accurate measurement of blood 16.

Hole 103 b is formed in advance in the ceiling face of storing part 49of blood sensor 103. In this way, hole 103 b is formed in advance, sothat it is not necessary to adjust the axis of the laser light to partto be perforated. Therefore, blood sensor 103 is easily attached toblood sensor unit 44. Hole 103 b may be made small, approximately 0.05to 0.25 mm, and preferably prevents blood 16 from flowing out throughthe puncturing hole.

As shown in FIG. 8 and FIG. 9, blood sensors 42 and 103 in blood testapparatus 31 and 31 a of the present invention preferably have storingpart 49 and supply channel 50. The inner wall surface of supply channel50 is preferably hydrophilic, so that blood is sent smoothly to supplychannel 50 where detecting section 51 is arranged. Further, the innerwall surface of supply channel 50 is preferably more hydrophilic thanthe inner wall surface of storing part 49, so that blood stored instoring part 49 is supplied to supply channel 50 smoothly.

Further, blood sensors 42 and 103 in blood test apparatuses 31 and 31 aof the present invention has cover 48 as shown in FIG. 8 and FIG. 9, andcover 48 forms the ceiling face of storing part 49. Upper faces 48 a and103 a (faces irradiated with laser light) of cover 48 are preferablywater-repellent. More practically, upper faces 48 a and 103 a of cover48 are preferably more water-repellent than the inner wall surface ofstoring part 49, so that blood stored in storing part 49 is preventedfrom flowing out through the hole (the hole perforated with laser lightor hole 103 b) formed on cover 48.

The Third Example of the Blood Sensor

The wetness of skin 13 of the patient varies depending on theenvironment.

On the other hand, skin 13 to be punctured with laser light preferablyhas a certain level of moisture content. Therefore, by moistening theneighborhood of skin 13 before puncturing with laser light, a certainlevel of wetness is preferably maintained by giving a certain level ofmoisture content to skin 13, so that measurement is performed in astable condition.

FIG. 11 shows blood sensor 42 a provided with water storing part 195that stores water, on the lower face side that abuts on skin 13, ofblood sensor 42 (see FIG. 8 in detail). When laser light is emitted orwhen the skin is lifted by negative pressure means 34 and 140 beforelaser light is emitted, water storing part 195 of blood sensor 42 ashown in FIG. 11 breaks to splash a certain amount of water on skin 13and moisten the skin. Water storing part 195 may be, for example, acontainer which contains water and which is made of a plastic materialsuch as PET, a soft bag, or a sponge or a spongy member that is soakedwith water. Water storing part 195 is preferably not arranged intransmission part 196 through which laser light transmits, because theintensity of the laser light is reduced by water.

Transparent Plan View 1 of the Blood Sensor

FIG. 12 is a transparent plan view of blood sensor 42. In blood sensor42, detection electrodes 54 to 57 are arranged, and in order fromstoring part 49 toward air hole 52, detection electrode 57 (Hct(hematocrit) electrode), detection electrode 56 (counter electrode),detection electrode 54 (active electrode) and detection electrode 55(sensing electrode) are arranged. Detection electrodes 54 to 56 arearranged in detecting section 51.

Detection electrodes 54 to 57 are connected to connection electrodes 54a to 57a, respectively. Connection electrodes 54 a to 57 a extend up tothe outer periphery of substrate 46. Contact parts 54 b to 57 b areprovided in connection electrodes 54 a to 57 a, respectively. Further,in connection electrode 56 a, contact part 56 c is also provided inaddition to contact part 56 b, that is, two contact parts are formed.Reference electrode 56 d may be provided in connection electrodes (54 a,55 a or 57 a) other than connection electrode 56 a.

Contact parts 54 b to 57 b and contact part 56 c are arranged near theouter periphery of sensor 42 at virtually regular intervals.

Out of contact parts 54 b to 57 b and 56 c, contact part 56 b andcontact part 56 c electrically conduct with each other, and the othercontact parts are insulated from each other.

The connection electrodes can be specified using contact part 56 c as areference contact part, that is, reference electrode 56 d. That is, theinsulation resistance between the neighboring contact parts is measuredby electrical circuit section 36 (see FIG. 2), and a contact part wherethe insulation resistance is zero is identified as reference electrode56 d. Based on reference electrode 56 d, connection electrodes 56 a, 57a, 54 a and 55 a are specified clockwise.

In this way, blood sensor 42 has reference electrode 56 d, so that it ispossible to specify the connection electrodes. Therefore, even if thecontact parts (54 b to 57 b and 56 c) are connected casually to the fiveconnectors arranged in apparatus body 39, it is possible to specify theconnection electrodes and perform measurement. Accordingly, blood sensor42 (or blood sensor unit 44 including blood sensor 42) can be made in asymmetrical shape so that blood sensor 42 can be attached to apparatusbody 39 casually in a very simple manner.

Aligning concave part 46 c may be provided on the outer periphery ofsubstrate 46. Corresponding to aligning concave part 46 c, on the outerperipheries of spacer 47 and cover 48, aligning concave parts 47 c and48 c are provided. By using aligning concave parts 46 c to 48 c, bloodsensor 42 can be attached to blood sensor unit 44 so as to meet apredetermined alignment of blood sensor unit 44.

Transparent Plan View 2 of the Blood Sensor

FIG. 13 is a transparent plan view of a round blood sensor. Blood sensor101 shown in FIG. 13 is different from blood sensor 42 (see FIG. 12) inthat reference electrode 56 d is formed via a predetermined pattern fromconnection electrode 56 a. The difference will be mainly describedbelow.

Reference contact part 56 c is provided in reference electrode 56 d.Reference contact part 56 c and contact parts 54 b to 57 b are arrangednear the outer periphery at regular intervals. That is, contact parts 54b, 55 b, 56 b, 56 c and 57 b are arranged at the apexes of a regularpentagon.

Connection electrode 56 a and reference electrode 56 d are connected vialaser-machined pattern 56 e. By changing the width of pattern 56 e, theresistance value between contact part 56 b and reference contact part 56c can be changed. Reference electrode 56 d serves as a reference forspecifying the positions of connection electrodes 54 a to 57 a.

Reference electrode 56 d can be utilized to identify the productspecifications of blood sensor 101. For example, the blood testapparatus is set so that calibration curve 1 is used when the resistancevalue of pattern 56 e is 200 to 1000 ohms, calibration curve 2 is usedwhen the resistance value is 1000 to 2000 ohms, and calibration curve 3is used when the resistance value is 2000 to 3000 ohms, the calibrationcurve of the sensor is recognized automatically, and the blood sugarlevel is measured using an appropriate calibration curve.

The reference electrode can be used to identify various productspecifications, in addition to use in automatic recognition of thecalibration curve. For example, the reference electrode can be used toidentify the users to whom the product is shipped, and to identifywhether the product has the specifications for company A or thespecifications for company B.

By forming an inductance using pattern 56 e, which may have variousvalues depending on pattern 56 e, connecting this inductance to aresonator constituting an oscillator and changing the oscillationfrequency according to these inductance values, various information isprovided.

By providing reference electrode 56 d, even when blood sensor unit 44 isattached to blood test apparatus 31 or 31 a at an arbitrary rotationangle with respect to the axis of the attaching direction, connectionelectrodes 54 a to 57 a can be specified. Therefore, when blood sensorunit 44 is attached, the attaching direction does not have to beadjusted with visual checking, so that it is possible to attach bloodsensor unit 44 in a simple manner.

Transparent Plan View 3 of the Blood Sensor

FIG. 14 is a transparent plan view of a square-shaped blood sensor.Although the outer shape of blood sensor 102 shown in FIG. 14 is asquare, the outer shape may be a polygonal such as a hexagon andoctagon. By forming blood sensor 102 in a square or hexagonal shape, thematerial yield is improved. Further, as shown in FIG. 14, concave part102 a for aligning blood sensor unit 44 may be provided in one of thefour sides of blood sensor 102, in such a case blood sensor 102 has anasymmetrical shape. Concave part 102 a serves as the reference whenblood sensor 102 is attached to blood sensor unit 44. Further, byaligning adapter 40 using as a reference convex part 130 f (see FIG. 25)in the blood sensor unit 44 side that engages with concave part 102 a,the positions of connection electrodes 54 a to 57 a can be specifiedeven if reference electrode 56 d is not provided.

Contact parts 54 b to 57 b are provided in the corners of square-shapedsubstrate 102 b. Spacer 102 c and cover 102 d are stacked on substrate102 b. Substrate 102 b corresponds to substrate 46, spacer 102 ccorresponds to spacer 47, cover 102 d corresponds to cover 48 (see FIG.8).

An Exploded Plan View of the Blood Sensor

An assembly and material of blood sensor 42 (see FIG. 8) provided inblood test apparatuses 31 and 31 a of the present invention will bedescribed.

FIG. 15 is an exploded plan view of blood sensor 42. FIG. 15A is a planview of cover 48, FIG. 15B is a plan view of spacer 47, and FIG. 15C isa plan view of substrate 46.

FIG. 15C is a plan view of round substrate 46 constituting blood sensor42. The diameter of substrate 46 maybe approximately 8.0 mm. Thematerial of substrate 46 is resin such as polyethylene terephthalate(PET), and its thickness may be 0.075 to 0.250 mm (for example, 0.188mm).

On the upper face of substrate 46, detection electrodes 54 to 57, andconnection electrodes 54 a to 57 a derived from respective detectionelectrodes 54 to 57 are formed in an integrated manner. These detectionelectrodes and connection electrodes may be formed by applying laserprocessing to a conductive layer which is formed using the sputteringmethod or the vapor deposition method. The material of the conductivelayer may be gold, platinum, or palladium.

The diameter of hole 46 a provided near the center of substrate 46 maybeapproximately 2.0 mm. Preferably, the wall surface of hole 46 a is lesshydrophilic than supply channel 50 or is less water-repellent than upperface 48 a of cover 48.

Hole 46 a is preferably formed by punching out substrate 46 from thedetection electrodes 54 to 57 side using a convex mold, because it isless likely to damage detection electrodes 54 to 57 if the punching isperformed from the detection electrodes 54 to 57 side. Further, even ifa burr is produced in hole 46 a by this punching, the burr is orienteddownward (toward the skin). Therefore, blood 16 is prevented fromflowing out from storing part 49. Concave part 46 c for aligningprovided on the outer periphery of substrate 46 engages with a aligningconvex part formed in cylindrical body 41 e of blood sensor unit 44 (seeFIG. 16). The position where blood sensor 42 is attached to blood sensorunit 44 is thereby determined.

FIG. 15B is a plan view of spacer 47. The diameter of spacer 47 may beapproximately 5.2 mm. The material of spacer 47 is resin such aspolyethylene terephthalate, and its thickness may be 0.025 to 0.25 mm(for example, 0.1 mm).

The diameter of hole 47 a provided near the center of spacer 47 is 2.0mm, and hole 47 a is provided at the position corresponding to hole 46 aprovided in substrate 46. Preferably, the wall surface of hole 47 a isless hydrophilic than supply channel 50 or is less water-repellent thanupper face 48 a of cover 48. Storing part 49 is constituted with hole 46a and hole 47 a.

Slit 47 b is formed toward the outer periphery from hole 47 a. Slit 47 bserves as blood supply channel 50. The wall surface of slit 47 b and theupper face of substrate 46 corresponding to the wall surface of slit 47b are subjected to hydrophilicity treatment. The width of slit 47 b maybe approximately 0.6 mm, and the length may be approximately 2.4 mm. Asa result, the volume of supply channel 50 is approximately 0.144 μL.

Therefore, by making the volume of supply channel 50 small, test can beperformed with a small amount of blood, so that the load on the patientbecomes small and the patient does not feel fear.

Concave part 47 c for aligning provided on the outer periphery of spacer47 is formed in the position corresponding to concave part 46 c foraligning provided in substrate 46.

FIG. 15A is a plan view of cover 48. The diameter of cover 48 may beapproximately 5.2 mm. The thickness of cover 48 may be approximately0.050 to 0.125 mm (for example, 0.075 mm).

Cover 48 can be made of a material that does not absorb laser light.Examples of the material of cover 48 include glass and plastic such aspolyimide. when laser light is not absorbed in cover 48, the laser lightcan pass through ceiling face 49 a of storing part 49 to puncture theskin. The laser light does not perforate ceiling face 49 a, and so blood16 does not flow out through the hole, nor it flows into apparatus body39.

Cover 48 may be made of a material that absorbs laser light. In thiscase, cover 48 may be perforated by the emitted laser light, or beforethe laser light is emitted, a hole through which the laser light passesmay be formed in cover 48.

Air hole 52 is provided to meet the tip part of supply channel 50. Thediameter of air hole 52 is 50 μm.

Upper face 48 a (see FIG. 8) of cover 48 that forms the upper face ofsubstrate 45 is preferably subjected to water-repellency treatment. Theceiling face of supply channel 50 is preferably subjected tohydrophilicity treatment. Further, preferably, ceiling face 49 a ofstoring part 49 is subjected to weaker hydrophilicity treatment thansupply channel 50 or is subjected to weaker water-repellency treatmentthan upper face 48 a of cover 48.

Hydrophilicity may be reduced by, for example, removing thehydrophilizing agent applied on a hydrophobic material to increasehydrophobicity. The hydrophilizing agent is removed by, for example,decomposing the hydrophilizing agent through UV (ultraviolet ray)irradiation. The hydrophobic material can be directly used as thematerial of ceiling face 49 a of storing part 49.

The material may be made water-repellent by mixing a water-repellentagent in the material. Further, the material may be made water-repellentby applying an appropriate amount of water-repellent agent on thesurface of the hydrophilic material. The level of water-repellency maybe adjusted by adjusting the amount of the water-repellent agent to bemixed.

The hydrophilicity or water-repellency of the components of blood sensor42 can be adjusted as follows.

Upper face 48 a of cover 48 is subjected to water-repellency treatmentin advance. On the other hand, the overall lower face of cover 48 issubjected to hydrophilicity treatment. The lower face of cover 48includes the ceiling face of supply channel 50. Next, substrate 46,spacer 47 and cover 48 are stacked. After substrate 46, spacer 47 andcover 48 are stacked, the hydrophilizing agent of ceiling face 49 emaybe dissolved and removed by radiating short-wavelength UV from theopening of storing part 49.

By manufacturing blood sensor 42 as described above, it is possible tomake upper face 48 a of cover 48 water-repellent and make the inner faceof supply channel hydrophilic. Further, the inner face of storing part49 may be less hydrophilic than supply channel 50 and lesswater-repellent than upper face 48 a.

The ratio of the thickness of substrate 46 (0.188 mm), the thickness ofspacer 47 (0.100 mm) and the thickness of cover 48 (0.075 mm) isapproximately, 2.5:1.3:1. By this means, it is possible to form storingpart 49 that can pool a sufficient amount of blood while making bloodsensor 42 thinner. Further, by the thickness of spacer 47 (0.100 mm),the effect of capillary action in supply channel 50 can be obtainedsufficiently.

In blood sensor 42, the ratio of the volume of storing part 49 (0.904μL) and the volume of supply channel (0.144 μL) may be approximately6:1, but the ratio is not particularly limited. By this means, test doesnot become incorrect, even when the amount of blood 16 is small.Further, the volume of storing part 49 is not too large with respect tothe needed volume of supply channel 50, and a large amount of blood 16does not flow into supply channel 50 and does not wash away reagent 53(see FIG. 8). Therefore, the rate of flow of blood 16 becomes constant,which does not generate variation in concentration of reagent 53, sothat it is possible to examine blood 16 accurately.

Further, the amount of blood 16 to be collected is set a very smallamount which is a sufficient amount required for a test of blood 16, andonly blood 16 of about six times the volume of supply channel 50 iscollected. Therefore, it is possible to reduce the load on the patientsignificantly. In view of the collection amount of blood 16 for accuratemeasurement and the collection amount of blood 16 for reducing the loadon the patient, the volume of storing part 49 is preferably more thanfive times and less than seven times the volume of supply channel 50.

The Blood Sensor Unit

Blood sensor 41 in blood test apparatuses 31 and 31 a of the presentinvention may be included in blood sensor unit 44. Blood sensor unit 44can be attached to and removed from apparatus body 39 and is areplaceable member.

FIG. 16 is a cross-sectional view of blood sensor unit 44 and theneighborhood of blood sensor unit 44. The cross section of blood sensorunit 44 is configured in the shape of “H” by cylinder-shaped holder 41that opens upward and downward, and attaching part 41 b that is providedso as to seal the interior of holder 41.

The material of holder 41 is preferably resin that is applicable toinjection molding, including ABS resin, AS resin and thermoplastic resinsuch as polyethylene, polypropylene, polyvinyl chloride and polyethyleneterephthalate, or thermosetting resin such as phenol resin, epoxideresin and silicon resin.

Blood sensor 42 is attached to attaching part 41 b. Blood sensor 42 canbe attached and removed. Although, in FIG. 16, blood sensor 42 isattached to an upper side (the laser emitting apparatus 33 side) ofattaching part 41 b, blood sensor 42 may be attached to a lower side(the punctured skin 13 side) of attaching part 41 b.

In the center of attaching part 41 b, window 43 is preferably providedso as to correspond to storing part 49. The area of the opening part ofwindow 43 is preferably larger than the area of the opening part ofstoring part 49. Further, negative pressure path 41 c passing throughthe upper side and the lower side of attaching part 41 b is provided.Negative pressure path 41 c may be provided, for example, between theouter periphery of blood sensor 42 and the inner periphery of holder 41.

Cylindrical body 41 d located below attaching part 41 b forms negativepressure chamber 60 between skin 13 and cylindrical body 41 d. Further,the inner wall of cylindrical body 41 e located above attaching part 41b of blood sensor unit 44 is latched outside adapter 40.

Connector 61 is provided inside adapter 40. Connector 61 includes aplurality of (for example, five) individual connectors 61 a to 61 e.When blood sensor unit 44 is attached to adapter 40, connectors 61 a to61 e contact with contact parts 54 b to 57 b and 56 c of blood sensor42, respectively. Signals of connectors 61 a to 61 e are led toelectrical circuit section 36.

First skin contact sensor 62 provided at tip 41 h of cylindrical body 41d detects skin 13 when blood sensor unit 44 abuts on skin 13. First skincontact sensor 62 also connects to connection part 62 c provided inadapter 40 via conductor 62 a arranged inside holder 41, and furtherconnects to conductor 62 b at the adapter 40 side. Conductor 62 b is ledto electrical circuit section 36.

First skin contact sensor 62 configured with a plurality of (forexample, two) conductors are preferably provided in different parts intip 41 h of cylindrical body 41 d (in FIG. 16, on a straight line thatpasses the center of cylindrical body 41 d). By measuring the resistancevalue between two conductors of first skin contact sensor 62, skin 13 isdetected when blood sensor unit 44 abuts on skin 13. Therefore, it ispossible to detect skin 13 when the tips of blood sensor unit 44 abut onskin 13 completely without space. Laser light is preferably not allowedto emit unless first skin contact sensor 62 detects a contact with theskin. First skin contact sensor 62 may be a mechanical micro switch or areflection optical switch.

By emitting laser light from laser emitting apparatus 33, bloodcapillaries in skin 13 are damaged by the laser light, and blood 16flows out. The outflow of blood 16 is stored in storing part 49.

A guide part for attaching blood sensor unit 44 in a simple manner maybe provided in cylindrical body 41 d and adapter 40 of blood sensor unit44. FIG. 17 is an exploded elevation view of the primary part of guidepart 63 that guides insertion of blood sensor unit 44 into adapter 40.Convex part 41 f is formed inside cylindrical body 41 d, and convex part40 f is formed outside adapter 40. Tip part 41 g and tip part 40 g,which are the tips of convex part 41 f and convex part 40 f,respectively, are made sharp. Tip part 41 g and tip part 40 f face eachother. Convex part 40 f and its tip part 40 g, and convex part 41 f andits tip part 41 g, constitute guide part 63.

When blood sensor unit 44 is inserted into adapter 40, even when thepositions of blood sensor unit 44 and adapter 40 are out ofpredetermined alignment, blood sensor unit 44 is inserted along guidepart 63 while correcting the course (see arrow 64). As a result,connectors 61 a to 61 e provided in adapter 40 are sure to contact withone of contact parts 54 b to 57 b and 56 c provided in sensor 42.Therefore, blood sensor unit 44 can be inserted without taking intoaccount the rotation angle with respect to the axis of the insertiondirection, so that blood sensor unit 44 can be attached in a simplemanner.

FIG. 18 is a diagrammatic perspective view of the blood sensor unit.Blood sensor unit 110 shown in FIG. 18 may have the same structure asblood sensor unit 44 unless described otherwise. Blood sensor unit 110has the shape of a cylinder, and its cross section has the shape of “H.”Five connectors 111 that transmit signals of the contact part of theblood sensor (one of blood sensors 42, 101, 102 and 103) to electricalcircuit section 36 may be provided inside holder 110 a of blood sensorunit 110 (in the case of blood sensor 102, four connectors may beprovided). Connector 111 connects to adapter 40 at an upper end ofholder 110 a and is led to electrical circuit section 36 via thisadapter 40.

Connector 111 may be provided in the adapter and may be connected withthe contact part of the blood sensor of blood sensor unit 110.

Blood sensor 42 is attached on the reverse side (the side of lower end110 h, that is, the side the punctured skin is arranged) of attachingpart 110 b provided so as to seal the opening of holder 110 a. Window110 c provided near the center of attaching part 110 b is provided so asto correspond to the position of storing part 49 of blood sensor 42.Laser light passes through window 110 c and storing part 49 andpunctures skin 13.

Air hole 110 d provided in attaching part 110 b is provided in theposition corresponding to air hole 52 of blood sensor 42. Air hole 110 dis provided to flow blood 16 into supply channel 50 of blood sensor 42or create a negative pressure in storing part 49.

Blood sensor unit 110 engages with adapter 40 using the elasticity ofengaging part 110 e which engages with adapter 40. Two engaging parts110 e that face each other are provided in holder 110 a. Engaging parts110 e have slits on both sides and thereby have elasticity, and areformed integrated with holder 110 a. Therefore, engaging parts 110 e canbe made at a low cost.

Deodorizing member storage 110 f is provided on the upper face ofattaching part 110 b in a concentric fashion. A deodorizing member isplaced on deodorizing member storage 110 f. When the skin is puncturedwith laser light, cases occur where skin 13 is carbonized and producesan odor. This odor can be deodorized with the deodorizing member (suchas deodorant agent). Further, blood pool 110 f is provided on the upperface of attaching part 110 b in a concentric fashion. Therefore, even ifblood 16 overflows from hole 103 b of blood sensor 103 (see FIG. 10),blood 16 stays in blood pool 110 g, so that it is possible to preventblood 16 from contaminating the body part of blood test apparatuses 31and 31 a.

FIG. 19 is a cross-sectional view showing the primary part of oneconfiguration example near lower end 110 h of holder 110 a. An end partof lower end 110 h abuts on skin 13 of the patient and forms negativepressure chamber 60. Lower end 110 h needs to closely contact with skin13. Therefore, lower end 110 h may be formed with two concentric lines110 j which are made sharp at an acute angle. Line 110 j abuts on skin13 completely by line contact, so that negative pressure chamber 60 iskept sealed. The number of lines 110 j does not have to be two, andthere may be one or a plurality of lines 110 j.

Further, if capillary action is given to a groove formed between twoconcentric lines 110 j, over-sampled blood 16 after measurement issucked in the groove. Therefore, it is not necessary to prepare paperfor wiping off over-sampled blood 16.

FIG. 20 is a cross-sectional view showing the primary part of anotherconfiguration example near lower end 110 h of holder 110 a. Concentricabutting part 110 k formed with elasticity such as rubber, silicon,urethane and a sponge, is formed in lower end 110 h. Therefore, abuttingpart 110 k is in close contact with skin 13 by its elasticity, andnegative pressure chamber 60 is kept sealed. The contact surface ofabutting part 110 k is preferably flat to increase the area whereabutting part 110 k abuts on skin 13.

By forming abutting part 110 k with an absorbing member, such as asponge, that has absorbency, it is possible to wipe off over-sampledblood 16 flown out by puncturing after measurement. Therefore, it is notnecessary to prepare wiping paper. Further, if an antiseptic is added tothe absorbing member, the absorbing member becomes sanitary.

The wetness of skin 13 changes with the external environment such asseasons. Therefore, the wetness near skin 13 to be punctured ispreferably maintained constant. Therefore, before puncturing,measurement may be performed in a stable condition by providing anadequate level of moisture content to skin 13 and moistening the skin.

Therefore, as shown in FIG. 21, it is also possible to provide waterstoring part 197 which is soaked with water, throughout the perimeter oflower end 110 h of holder 110 a of blood sensor unit 110, soak skin 13near the part to be punctured with water in advance and puncture skin 13with laser light. Water storing part 197 maybe a porous material thathas elasticity such as a sponge.

FIG. 22 is a cross-sectional view of blood sensor unit 110. As shown inFIG. 22, blood sensor 42 is arranged in the lower face of attaching part110 b of blood sensor unit 110 and is held by attaching part 110 b. Skin13 is lifted by negative pressure means 34 and 140 (see FIG. 2 and FIG.3) and is inclose contact with blood sensor 42. Blood sensor 42 is heldby attaching part 110 b, and so is less likely to be distorted by skin13 that is in close contact with blood sensor 42. Connectors 111 contactwith contact parts 54 b to 57 b and 56 c of blood sensor 42. Guide part63 (see FIG. 17) for adapter 40 is preferably provided in holder 110 a.

Blood test apparatuses 31 and 31 a of the present invention has negativepressure means 34 and 140, and negative pressure means 34 and 140 createa negative pressure inside blood sensor unit 110. As a negative pressurepath, groove 110 f may be formed in attaching part 110 b of blood sensorunit 110. Groove 110 f extends to window 110 e formed near the center ofattaching part 110 b, from the outer periphery side of attaching part110 b of holder 110 a. When a negative pressure is created, a negativepressure is also created in groove 110 f, and blood sensor 42 is inclose contact with attaching part 110 b. When the negative pressure isreleased to the atmosphere, blood sensor 42 is removed from attachingpart 110 b.

Connectors 111 contact with blood sensor 42 in contact surface 111 a.Connectors 111 are incorporated in holder 110 a and formed so as to cutinto part of attaching part 110 b. By this means, the contact parts ofthe connection electrodes formed on the upper face of blood sensor 42connect with contact parts (not shown) provided in connectors 111.

Second skin contact sensor 110 m may be provided in the lower face ofblood sensor 42. By this means, skin 13 is detected when skin 13 abutson second skin contact sensor 110 m by the negative pressure generatedin negative pressure chamber 60. Second skin contact sensor 110 m maybe, for example, configured with a counter electrode. Laser lightemission is preferably not allowed unless second skin contact sensor 110m detects a contact with the skin.

Negative pressure means 34 may stop creating a negative pressure innegative pressure chamber 60 when second skin contact sensor 110 m isdetected to abut on skin 13. By controlling negative pressure means 34in this way, negative pressure means 34 can be controlled withoutwasting a negative pressure power.

Further, first skin contact sensor 62 may be provided in lower end 110 hof holder 110 a.

FIG. 23 is a cross-sectional view of another blood sensor unit. Bloodsensor unit 120 shown in FIG. 23 may have the same structure as bloodsensor unit 110 unless described otherwise. Blood sensor unit 120 isdifferent from blood sensor unit 110 in that blood sensor 42 is mountedon the upper side of attaching part 120 b formed so as to seal theopening of holder 120 a. Connectors 61 connected to electrical circuitsection 36 conduct with contact parts (54 b to 57 b and 56 c) of bloodsensor 42.

The upper space and the lower space in attaching part 120 b of bloodsensor unit 120 having an H-shaped cross section, communicate throughnegative pressure path 120 c. The lower space forms negative pressurechamber 60. First skin contact sensor 62 is provided in lower end 120 hof holder 120 a. Further, although not shown, second skin contact sensor120 m may be provided in the lower face of attaching part 120 b.

By attaching blood sensor 42 on the upper face of attaching part 120 b,it is possible to increase contact pressures between connectors 61 andthe contact parts (54 b to 57 b and 56 c) of blood sensor 42 larger.Further, it is possible to attach blood sensor 42 to attaching part 120b in a simple manner.

Separated by blood sensor 42 and attaching part 120 b, the space on theside of apparatus body 39 (the upper space in the figure) and the spaceon the side of skin 13 (the lower space in the figure), communicate witheach other via negative pressure path 120 c. On creating a negativepressure on skin 13, it is possible to create a negative pressure in thespace on the side of skin 13 via this negative pressure path 120 c.Further, when a negative pressure is released to the atmosphere,airflows into space on the side of apparatus body 39 quickly vianegative pressure path 120 c. Therefore, it is possible to prevent bloodled in blood sensor 42 from dispersing on the apparatus body 39 side.

Groove 120 f may be formed on the upper side of attaching part 120 b asa negative pressure path. Groove 120 f extends from the outer peripheryof attaching part 120 b of holder 120 a to window 120 e formed near thecenter of attaching part 120 b. Providing groove 120 f makes itunnecessary to provide a hole (negative pressure path 120 c) whichpenetrates attaching part 120 b.

FIG. 24 is a cross-sectional view of another blood sensor unit. Bloodsensor unit 130 shown in FIG. 24 may have the same structure as bloodsensor unit 44 unless described otherwise. Here, blood sensor 42 isattached on the upper face of attaching part 130 b of blood sensor unit130. The inner diameter of lower end 130 d of holder 130 a is smallerthan the inner diameter of upper end 130 c.

The diameter of opening part 130 e of negative pressure chamber 60formed on the lower side of attaching part 130 b is preferably 2 to 20mm, more preferably, 3 to 10 mm, and, even more preferably, 5 to 7 mm,so that a negative pressure is created on the skin to be punctured moreefficiently. Further, by making the outer shape of lower end 130 dsmaller than the outer shape of upper end 130 c, it is possible to stacka plurality of blood sensor units 130 vertically and accommodate bloodsensor units 130 efficiently. Generally, blood sensor 42 needs to have acertain size, and so the outer shape of upper end 130 c is difficult tobe made smaller.

Further, locking convex part 130 g provided inside holder 130 a so as toproject toward blood sensor 42, latches blood sensor 42 and preventsblood sensor 42 from being removed from holder 130 a.

FIG. 25 is a plan view of blood sensor unit 130. Two convex parts 130 fthat fit concave parts 46 c and 47 c (see FIG. 15) for aligning bloodsensor 42 are formed in holder 130 a of blood sensor unit 130 (at anangle of approximately 120 degrees). The position where blood sensor 42is arranged in blood sensor unit 130 is determined by convex part 130 fof holder 130 a and concave part 46 c of blood sensor 42. Blood sensorunit 130 where blood sensor 42 is arranged adequately is attached toadapter 40 in a predetermined position by guide part 63 (see FIG. 17).In this way, signals of detection electrodes 54 to 57 of blood sensor 42are transmitted to electrical circuit section 36.

There may be one convex part 130 f, but, in that case, attaching part130 b preferably has a structure that allows blood sensor 42 to be fitin.

The Focus of Laser Light

Blood test apparatuses 31 and 31 a of the present invention uses laserlight as a puncturing means, and, laser emitting apparatus 33 isaccommodated in apparatus body 39 (see FIG. 2, for example). The emittedlaser light is focused by a focus lens and emitted on skin 13. In bloodtest apparatuses 31 and 31 a of the present invention, laser light ispreferably focused near the surface of blood sensor 42, for example. Asdescribed above, skin 13 to be punctured is sucked in by negativepressure means 34 and 140 and is in close contact with blood sensor 42,so that the laser light focused near the surface of blood sensor 42 canpuncture skin 13 effectively.

The focus of the laser light may be on the surface of blood sensor 42,and may be closer to skin 13 than the surface of blood sensor 42 orcloser to laser emitting apparatus 33 than the surface of blood sensor42. FIG. 26 shows a result of examining using a laser alignment paper(ZAP-IT corporation: Z-48), the relationship between the “burn patterndiameter (mm)” (Y axis) and the “distance (mm) from the laser focus tothe target to be punctured (the puncturing target, which in this case isthe laser alignment paper)” (X axis). The “burn pattern diameter” is thediameter of the hole which is opened when laser light is emitted.

FIG. 26 is a graph showing the relationship between the distance (Xaxis) from the focus position of laser light to the puncturing targetand the burn pattern diameter (Y axis), in the blood test apparatus ofthe present invention.

In the X axis in the graph shown in FIG. 26, “0” is the focus positionof laser light. The negative (“−”) domain applies to cases where theposition of the puncturing target is set closer to laser emittingapparatus 33 than the focus position of laser light, and the positive(“+”) domain applies to cases where the position of the puncturingtarget is set farther from laser emitting apparatus 33 than the focusposition of laser light.

The laser output intensity includes four types of 60 mJ, 80 mJ, 100 mJand 120 mJ. Although the burn pattern diameter becomes greater inproportion to the output intensity, the relationship between thedistance (X) from the focus to the puncturing target and the burnpattern diameter (Y) is similar between all output intensities.

In zone A (when the focus is adjusted near the puncturing target), evenwhen the position of the puncturing target shifts somewhat, the burnpattern diameter does not change significantly. Therefore, it ispossible to puncture the skin reliably. On the other hand, in zone B orzone C, the burn pattern diameter changes significantly by the shift ofthe position of the puncturing target. In a case that the focus positionof laser light shifts, the burn pattern diameter change in the samemanner, because the focus position of laser light has a relativerelationship with the position of the puncturing target.

That is, when the position of the puncturing target is fixed, forexample, in zone A (when the focus is adjusted near the puncturingtarget), even if the focus position of laser light shifts somewhat, theburn pattern diameter does not change significantly. Therefore, it ispossible to puncture the skin reliably. On the other hand, in zone B orzone C, when the focus position of laser light shifts, the burn patterndiameter changes significantly.

If the focus position of laser light shifts so as to increase the burnpattern diameter, the skin is not punctured, so that safety improves.For example, if the focus position of laser light is adjusted in zone B,unless the position of the puncturing target approaches the positionfrom which the laser light is emitted, up to a predetermined position,the skin is not punctured. That is, unless the skin is sucked in andlifted sufficiently by a negative pressure, the skin is not punctured.

By adjusting the focus position of the laser light in zone C, when theposition of the puncturing target comes closer to the position fromwhich the laser light is emitted, than a predetermined position, theskin is not punctured. That is, even if the skin is sucked in and liftedmore than necessary by a negative pressure, the skin is not punctured.

Further, when a film prone to melt is arranged in blood sensor 42, thereis a case where the focus is not preferably adjusted on blood sensor 42,because the film melts and energy of laser light is consumed. Therefore,there is a case where the focus is preferably adjusted in zone B or zoneC.

The Negative Pressure Chamber

Blood test apparatuses 31 and 31 a of the present invention has negativepressure means 34 and 140, and, apparatus body 39 accommodatesmechanical suction pump 34 a (FIG. 2) or manual suction pump 141 (FIG.3) as one component of negative pressure means 34 and 140. Negativepressure means 34 and 140 create a negative pressure in negativepressure chamber 60 and suck in and lift skin 13, which is the part tobe punctured, thereby placing skin 13 in close contact with blood sensor42.

As described above, negative pressure means 34 is configured withsuction pump 34 a, pump valve unit 34 b and vent switch 34 c (see FIG.2). Negative pressure means 140 is configured with manual pump 141 andmanual pump knob 142 in addition to pump valve unit 143 and vent switch144 (see FIG. 3). In a broad sense, the term “negative pressure means”includes the negative pressure path in addition to the pump (a suctionpump or a negative pressure pump) and the valve (a negative pressurevalve or an open valve). Further, here, “driving the negative pressuremeans” means driving the pump and the valve, and “releasing the negativepressure” means opening the valve and introducing an outside atmosphericpressure (for example, atmospheric pressure).

FIG. 27 and FIG. 28 show a negative pressure chamber (suction chamber)and a negative pressure path. FIG. 27 shows a negative pressure path fora case where the negative pressure chamber is the largest, and FIG. 28shows a negative pressure path for a case where the negative pressurechamber is the smallest. Explaining blood test apparatus 31 in FIG. 2 asan example, both suction chamber 60 a shown in FIG. 27 and suctionchamber 60 b shown in FIG. 28 are internal space of apparatus body 39,and provided in space closer to blood sensor 42 than laser emitting port33 c of laser emitting apparatus 33. Negative pressure chamber 60 widelyrefers to space where skin 13 abuts on blood sensor unit 44 and anegative pressure is created upon measurement, and includes internalspace of blood sensor unit 44 in addition to suction chambers 60 a and60 b in apparatus body 39. As shown in FIG. 27 and FIG. 28, negativepressure chamber 60 (particularly, suction chambers 60 a and 60 b) is,for example, vacuumed by pump 34 a (that is, a negative pressure iscreated), and a negative pressure is released by valve 34 b.

If negative pressure chamber 60 is small, the energy required forcreating a negative pressure is reduced, and the time required for theblood test is also reduced. Therefore, negative pressure chamber 60(particularly, suction chambers 60 a and 60 b) inside blood testapparatuses 31 and 31 a of the present invention is preferablypartitioned by a wall provided closer to blood sensor 42 than laseremitting port 33 c of laser emitting apparatus 33.

To be more specific, wall (partition or dividing wall for a negativepressure) 70 that partitions suction chambers 60 a and 60 b may bearranged in the same position as laser emitting port 33 c, or in thesame position as focus lens 33 h (that is, the wall and focus lens 33 hare integrated), or focus lens 33 h itself may serve as a wall. Examplesshown in FIG. 27 and FIG. 28 show the latter case. Further, to reducethe volume of negative pressure chamber 60, the shape of the suctionchamber may be a cone (see suction chamber 60 b in FIG. 28). Apparatusbody 39 has negative pressure path 71 that communicates with suctionchambers 60 a and 60 b, and this negative pressure path 71 is connectedto the suction port of pump 34 a. As described above, storing part 49,supply channel 50 and air hole 52 which also function as negativepressure path 72, are provided inside blood sensor 42. Suction chambers60 a and 60 b also communicate with this negative pressure path 72 inblood sensor 42. Particularly, in a configuration example of FIG. 28,fine negative pressure path 73 that connects suction chamber 60 b andair hole 52 is further provided in apparatus body 39. Negative pressurepaths 72 and 73 (except part of storing part 49) are micro-channels, thevolumes of which are almost zero.

As shown in FIG. 29 and FIG. 30, in blood test apparatuses 31 and 31 a,there are at least three internal spaces V₁, V₂ and V₃ as the internalspace including the path of laser light 80. Internal space V₁ is thespace between the front surface of laser crystal (laser rod) 33 d andfocus lens 33 h. Internal space V₂ is the space between focus lens 33 hand blood sensor 42 (or holder 41) in blood sensor unit 44, andcorresponds to suction chambers 60 a and 60 b in apparatus body 39 inthe configuration examples in FIG. 27 and FIG. 28. Internal space V₃ isthe space between blood sensor 42 (or holder 41) in blood sensor unit 44and skin abutting surface 74, and mainly corresponds to the internalspace of blood sensor unit 44.

For example, the diameter of focus lens 33 h is φ5 to 15 mm. Thedistance from focus lens 33 h to blood sensor 42 is 10 to 30 mm.Further, the distance from blood sensor 42 to the lower face (=skincontact surface) of holder 41 is 1.5 to 2 mm, and the diameter of bloodsensor 42 and holder 41 is φ6 to 10 mm. Negative pressure chamber 60shown in FIG. 27 is configured with V₂ and V₃. When the volume ofsuction chamber 60 a is made a maximum, actually, there would be littleinclining part in the internal shape of apparatus body 39, and so thepart of V₂ can be made similar to a cylindrical shape in a simplemanner. The part of V₃ is also in a cylindrical shape. Therefore, inthis case, the volume can be made approximately 5.5 cc (see areasurrounded by a dotted line in FIG. 29). Further, negative pressurechamber 60 shown in FIG. 28 is also configured with V₂ and V₃. When thevolume of suction chamber 60 b is made a minimum, the part of V₂ has theshape of a cone, the part of the negative pressure path need not betaken into account, and the part of V₃ is the same as described above,and so the volume can be made approximately 0.45 cc (see area surroundedby a dotted line in FIG. 30).

The Electrical Circuit

FIG. 31 is a block diagram of electrical circuit section 36. In FIG. 31,54 b to 57 b and 56 c are contact parts formed in blood sensor 42.Contact parts 54 b to 57 b and 56 c are connected to switch circuit 71via connectors 61 a to 61 e. The output of switch circuit 71 isconnected to the input of current/voltage converter 72. The output ofcurrent/voltage converter 72 is connected to the input of calculatingsection 74 via analogue/digital converter (hereinafter A/D converter)73. The output of calculating section 74 is connected to display section37 formed with liquid crystal. Further, reference voltage supply 78 isconnected to switch circuit 71. Reference voltage supply 78 may provideground potential.

The output and input of controlling section 76 is connected to a controlterminal of switch circuit 71, calculating section 74, puncture button75, transmitting section 77, timer 79, laser emitting apparatus 33,negative pressure means 34 (particularly, suction pump 34 a) and firstskin contact sensor 62, and also connected to a warning means (notshown) and second skin contact sensor 110 m (see FIG. 22). Further, theoutput of calculating section 74 is also connected to the input oftransmitting section 77. The suction port of negative pressure means 34(particularly, pump valve unit 34 b) is led inside negative pressurechamber 60 and blood sensor unit 44 via negative pressure path 71.

The operation of electrical circuit section 36 will be described.

Before a blood test, it is specified to which of connectors 61 a to 61e, respective contact parts 54 b to 57 b and 56 c of blood sensor 42 areconnected. First, by the command from controlling section 76, out ofconnectors 61 a to 61 e, contact part 56 c where electrical resistancebetween the neighboring terminals is zero, is specified. A connectionelectrode connected to specified contact part 56 c is determined asreference electrode 56 d. Using connector 61 connected to contact part56 c as a reference, connectors 61 connected to connection electrodes 56a, 57 a, 54 a and 55 a, are specified in order. In this way, connectors61 connected to connection electrodes 54 a to 57 a are specified.

Then, a blood test is conducted. Next, switch circuit 71 is switched,and detection electrode 54 as an active electrode for measuring theamount of blood components is connected to current/voltage converter 72via connectors 61 determined as described above. Further, detectionelectrode 54, which serves as a sensing electrode for detecting theinflow of blood 16, is connected to reference voltage supply 78 viaconnectors 61 determined as described above.

A certain voltage is applied between detection electrode 54 anddetection electrode 55. When blood 16 flows into detecting section 51 inthis state, a current flows between detection electrode 54 and detectionelectrode 55. This current is converted to a voltage by current/voltageconverter 72, and the voltage value is converted to a digital value byA/D converter 73. The digital value is outputted to calculating section74. Calculating section 74 detects a sufficient inflow of blood 16 basedon the digital value.

When blood 16 is not detected at detecting section 51 after apredetermined time has passed or when the amount of blood 16 is notadequate, a warning means maybe started for warning, and the treatmentmaybe displayed on display section 37.

Next, glucose, which is a blood component, is measured. The glucosecontent is measured by, first, switching switch circuit 71 by thecommand from controlling section 76 and connecting detection electrode54, which serves as the active electrode for measuring the glucosecontent, to current/voltage converter 72 via connectors 61. Further,detection electrode 56, which serves as the counter electrode formeasuring the glucose content, is connected to reference voltage supply78 via connectors 61.

For example, while the glucose in blood and the oxidation-reductionenzyme are reacted for a certain period, current/voltage converter 72and reference voltage supply 78 are turned off. After a certain period(1 to 10 seconds) has passed, by the command from controlling section76, a certain voltage (0.2 V to 0.5 V) is applied between detectionelectrode 54 and detection electrode 56. The current flowing betweendetection electrode 54 and detection electrode 56 is converted to avoltage by current/voltage converter 72. This voltage value is convertedto a digital value by A/D converter 73. This digital value is outputtedto calculating section 74. Calculating section 74 calculates the glucosecontent based on this digital value.

After the glucose content is measured, the Hct (hematocrit) level ismeasured.

First, by the command from controlling section 76, switch circuit 71 isswitched. Detection electrode 57, which serves as the active electrodefor measuring the Hct level, is connected to current/voltage converter72 via connectors 61. Further, detection electrode 54, which serves asthe counter electrode for measuring the Hct level, is connected toreference voltage supply 78 via connectors 61.

Next, by the command from controlling section 76, a certain voltage (2Vto 3V) is applied between detection electrode 57 and detection electrode54. The current flowing between detection electrode 57 and detectionelectrode 54 is converted to a voltage by current/voltage converter 72.This voltage value is converted to a digital value by A/D converter 73.This digital value is outputted to calculating section 74. Calculatingsection 74 calculates the Hct level based on this digital value.

Using the calculated Hct level and the glucose content, and, withreference to a calibration curve or a calibration table, which wascalculated in advance, the glucose content is corrected with the Hctlevel. The corrected result is displayed on display section 37.

Further, the corrected result maybe transmitted from transmittingsection 77 to an injection apparatus that injects insulin (used as anexample of a curative drug). The result may be transmitted by radio, butis preferably transmitted via optical communication which does notinterfere with medical equipment. If the injection apparatus can set thedose of insulin automatically based on the measured data transmitted tothe injection apparatus, the patient does not have to set the dose ofinsulin to be administered in the injection apparatus, which alleviatesthe inconvenience of the setting. Further, the dose of insulin can beset in the injection apparatus without involving an artificial means, sothat it is possible to prevent human setting errors.

Although a case has been described above where glucose is measured usingblood test apparatuses 31 and 31 a of the present invention, blood testapparatuses 31 and 31 a of the present invention are suitable for use inmeasurement of blood components (such as the lactate level andcholesterol) other than glucose.

Flow 1 of Measurement Steps

The flow of a blood test using blood test apparatus 31 shown in FIG. 2will be described with reference to FIG. 32.

First, blood sensor unit 44 is attached to blood test apparatus 31 (step81). In this step 81, blood sensor unit 44 is inserted into adapter 40.By this insertion, the tip of adapter 40 abuts on attaching part 41 b ofblood sensor unit 44. Blood sensor unit 44 is latched to adapter 40 byelasticity of holder 41.

Next, connection electrodes 54 a to 57 a of blood sensor 42 arespecified (step 82). Here, reference electrode 56 d is specified fromresistance values between neighboring connectors 61 a to 61 e inelectrical circuit section 36. From specified reference electrode 56 d,connection electrodes 56 a, 57 a, 54 a and 55 a are specified clockwise.In this way, connection electrodes 54 a to 57 a of blood sensor 42 ofblood sensor unit 44 inserted at an arbitrary angle are specified instep 82, and, as a result, detection electrodes 54 to 57 are specified.

Next, tip 41 h of blood sensor unit 44 is pressed against skin 13 of thepatient and is brought into close contact with skin 13 (step 83). Whenfirst skin contact sensor 62 detects a contact between skin 13 and tip41 h, suction pump 34 a of negative pressure means 34 operates andstarts creating a negative pressure. At this time, it is also possibleto detect the load current applied to suction pump 34 a with controllingsection 76, and display on display section 37 whether or not a negativepressure is enough for puncturing. Instead of detecting a load current,it is possible to measure with timer 79 a predetermined time from when anegative pressure is created and display on display section 37 whetheror not puncturing is possible.

Further, if second skin contact sensor 110 m as shown in FIG. 22 isprovided, it is possible to detect a lift of skin 13 by suction of anegative pressure. The detected result may be displayed on displaysection 37.

In this way, if a negative pressure is created on skin 13 when skin 13is punctured with laser light, skin 13 that has been relaxed before isplaced in a state of tension, so that it is possible to collect blood 16efficiently even if the prick by the puncturing is small. Therefore, thepain of the patient is alleviated. Further, by lifting skin 13 to apredetermined position by a negative pressure and specifying(controlling) the position of skin 13, it is possible to focus theemitted laser light correctly.

Next, puncture button 75 is pressed (step 84). A signal of puncturebutton 75 is recognized in electrical circuit section 36. Whenelectrical circuit section 36 starts laser emitting apparatus 33, laserlight is emitted toward skin 13. By setting the puncturing voltage ofthe laser light approximately 300 V, the pain the patient feels isalleviated.

Next, blood is collected (step 85). Blood 16 flowing out from skin 13 ofthe patient, punctured with the laser light, is stored in storing part49 of blood sensor 42 (see FIG. 8, for example). Blood 16 stored instoring part 49 intrudes into supply channel 50 by capillary action andis led to detecting section 51. When blood 16 led to detecting section51 reaches detection electrode 55 as the sensing electrode, it isdetermined that the amount of blood 16 required for measurement isobtained. At this time, negative pressure means 34 may be stopped, ornegative pressure means 34 may be stopped after skin contact sensor 62detects a non-contact of the skin.

On the other hand, when blood 16 is not detected at detecting section 51after a predetermined time has passed or when the amount of blood 16 isnot adequate (which is detected using the resistance between detectionelectrode 54 and detection electrode 55), a warning means maybe startedfor warning, and the appropriate measures may be displayed on displaysection 37.

Next, glucose is measured (step 86). After glucose in blood and glucoseoxidation-reduction enzyme are reacted for a certain period, glucosemaybe measured by applying a voltage between detection electrode 54 asthe active electrode and detection electrode 56 as the counterelectrode.

Further, the Hct level is measured (step 87). When a voltage is appliedbetween detection electrode 57 as the active electrode and detectionelectrode 54 as the counter electrode, a current that depends on the Hctlevel is detected. The Hct level is measured based on this current.

Finally, the blood components are corrected (step 88). That is, usingthe Hct level measured in step 87, the glucose content calculated instep 86 is corrected. The corrected result is displayed on displaysection 37. When measurement of the blood sugar level is finishedthrough the above-described steps, blood sensor unit 44 after use isdiscarded.

Flow 2 of Measurement Steps

FIG. 33 schematically illustrates a flowchart of measuring steps in moredetail.

In FIG. 33, step 151 shows a state before blood sensor unit 44 isattached to adapter 40 of blood test apparatus 31. Step 152 shows astate where blood sensor unit 44 is inserted into adapter 40 along guidepart 63 (see FIG. 7). Step 153 shows a state where connectors 61 arepressed and connectors 61 abut on contact parts 54 b to 57 b and 56 c ofsensor 42.

Next, the flow shifts to step 154, and a main switch of blood testapparatus 31 is turned on. Electrical circuit section 36 detectsreference electrode 56 d automatically and specifies detectionelectrodes 54 to 57. Display section 37 then displays that preparationfor measurement is completed.

In step 155, the end part of blood sensor unit 44 of blood testapparatus 31 is made to abut on skin 13. In FIG. 33, after step 155,apparatus body 39 of blood test apparatus 31 is omitted, and only bloodsensor unit 44 is shown. In step 156, blood test apparatus 31 is made toabut on skin 13 of the patient. First skin contact sensor 62 detectsskin 13 when blood test apparatus 31 abuts on skin 13.

When first skin contact sensor 62 detects skin 13, the flow shifts tostep 157. In step 157, negative pressure means 34 starts operating, andvacuums negative pressure chamber 60 as shown by arrow 157 a. As aresult of the suction, skin 13 is lifted. In the case of manual negativepressure means 140 (see FIG. 3), display section 37 displays start ofmanual operation, and the patient starts operating manual pump knob 142.

When a negative pressure is created, skin 13 is further lifted as shownin step 158 and abuts on second skin contact sensor (skin contactelectrode) 110 m.

Second skin contact sensor 110 m is formed on the reverse side of bloodsensor 42 attached on the lower face of blood sensor unit 44 (see FIG.22), or formed on the lower face of attaching part 120 b (see FIG. 23)in a case that blood sensor 42 is attached on the upper face of bloodsensor unit 44.

Second skin contact sensor 110 m only has to detect a contact betweenskin 13 and blood sensor 42, and, for example, an optical sensor, amechanical switch or an electrical resistance detection element may beused instead of an electrode.

In step 159, suctioning of skin 13 in negative pressure chamber 60 isstopped. When second skin contact sensor 110 m is not provided, thesuction may be stopped after a predetermined time has passed sincenegative pressure means 34 started operating. The time passed may bemeasured with timer 79 of electrical circuit section 36.

Next, the flow shifts to step 160, and skin 13 is irradiated with laserlight and punctured. By this puncturing, blood 16 flows out from skin13. Skin 13 may be punctured automatically when second skin contactsensor 110 m detects skin 13. Alternatively, it is also possible toallow the patient to press puncture button 75 (see FIG. 29) according toa display on display section 37 that blood sensor unit 44 abuts on skin13. When the patient presses puncture button 75, the patient can getready for puncturing.

As shown in step 161, blood 16 flowing out from skin 13 fills storingpart 49 and flows into supply channel 50. Blood 16 flows into supplychannel 50 by capillary action in supply channel 50 and suction throughair hole 52 by negative pressure means 34.

As shown in step 162, blood 16 is led to detecting section 51 of bloodsensor 42. When the inflow of blood 16 into detecting section 51 isdetected, the operation of negative pressure means 34 is stopped (step163). When blood 16 reaches detection electrode 55 (see FIG. 12) ofsensor 42, the inflow of blood 16 is detected. Then, vent switch 34 c isoperated, and the pressure in negative pressure chamber 60 is made equalto the outside atmospheric pressure.

Next, as shown in step 164, blood test apparatus 31 is released fromskin 13. When measurement is finished, display section 37 displays thatthe measurement is finished. Then, the flow shifts to step 165, anddisplay section 37 displays the result of measuring collected blood 16.

Flow 3 of Measurement Steps (Including Authentication Seps)

The flow of a blood test using the blood test apparatus of the presentinvention may include the steps of authenticating the user (i.e. , thepatient), so that a party other than the authorized party is not allowedto use in view of safety, given that the blood test apparatus is laserequipment.

FIG. 34 shows a flow of a test including authentication step 261.Whether or not the patient is a predetermined authorized party may beauthenticated using fingerprints, voice prints, iris and vein patterns,for example.

When the patient is authorized to use the apparatus, the flow proceedsto step 262. The patient sets the depth of puncturing (i.e., laserpower) by operating dials. Then, the flow shits to step 263, and bloodsensor unit 44 including blood sensor 42 is attached to adapter 40 ofblood test apparatus 31. Apparatus body 39 automatically starts uponattachment of blood sensor unit 44 and enters a measurement standbystate. It is also possible to perform step 263 of attaching blood sensorunit 44 before step 261. Although the measurement operation cannot beperformed unless blood sensor unit 44 is attached, it is possible todisplay the measurement result.

Next, the flow proceeds to step 264. In step 264, first skin contactsensor 62 (see FIG. 16, for example) detects whether or not blood sensorunit 44 abuts on skin 13. Instead of using first skin contact sensor 62,the presence or absence of a blood vessel, the body temperature, theelectrical resistance of the skin, or pulse, may be detected. In anycase, in view of safety, the operations from step 265 are performed whena state where blood sensor unit 44 abuts on skin 13 is detected. Theapparatus waits in step 264 until blood sensor unit 44 can be detectedto abut on skin 13.

When first skin contact sensor 62 detects the skin, the operation ofnegative pressure means 34 is started in step 265. Further, a drivevoltage of laser emitting apparatus 33 starts being charged at the sametime. The flow then proceeds to step 266, and the value of the currentflowing into negative pressure means 34 is monitored for 1 to 5 seconds.When the current value is not normal, display section 37 displays thatthe current value is not normal, and the flow returns to the step beforestep 264.

When the current value is normal, the flow proceeds to step 267, andwhether or not the negative pressure is adequate is determined. Whetheror not the negative pressure is adequate is determined by comparing thecurrent flowing into negative pressure means 34 with a predeterminedthreshold. When the negative pressure reaches a certain level, the flowproceeds to step 268, and emission of laser light is allowed. When thenegative pressure does not exceed the threshold, assuming an air leakage(i.e., poor contact between blood sensor unit 44 and skin 13), suctionby negative pressure means 34 is stopped and a retry is commanded, andthen the flow returns to the step before step 264.

Further, by arranging second skin contact sensor 110 m (see FIG. 22), itis possible to detect the lift of skin 13 sucked in by a negativepressure. When skin 13 is lifted adequately and is in close contact withblood sensor 42, emission of laser light is allowed.

In step 268, laser light is emitted and punctures skin 13. The flow thenproceeds to step 269, and blood 16 flowing out from skin 13 bypuncturing is led into blood sensor 42. At this time, negative pressuremeans 34 continues to be driven.

Next, the flow proceeds to step 270, and whether or not blood 16 is ledinto detecting section 51 (see FIG. 8) of blood sensor 42 is checked.Within a certain time (for example, 2 to 10 seconds) after puncturing,whether or not blood 16 reaches detection electrode 55 is detected. Whenblood 16 is not detected within a certain time, the flow returns to thestep before step 264, and the skin is punctured again. Therefore, bloodsensor 42 once attached is not wasted without being used. In addition,it is possible to quickly puncture the skin again.

When blood 16 is detected, the flow proceeds to step 271, and the bloodsugar level starts being measured. Further, in step 271, the negativepressure starts being released to the atmosphere by controlling pumpvalve unit 34 b (see FIG. 2). At this time, negative pressure meansstill operates, so that the patient learns that measurement is inprogress from sound and vibration produced while negative pressure means34 is driven, and the patient does not release blood test apparatus 31from skin 13. This prevents vibration and shock from being applied toblood test apparatus 31 during measurement of the blood components andrealizes stable measurement. Further, this prevents the patient fromreleasing the apparatus from skin 13 immediately after the negativepressure is released, and prevents blood 16 from splashing andcontaminating the surrounding.

When the measurement is finished in step 271, the flow shifts to step272, and display section 37 displays the measurement result. The flowthen shifts to step 273, and negative pressure means 34 (particularly,suction pump 34 a and pump valve unit 34 b) (see FIG. 2) stops beingdriven. Afterward, the patient releases blood test apparatus 31 fromskin 13.

Next, the flow shifts to step 274, and the patient removes blood sensorunit 44 from apparatus body 39 of blood test apparatus 31 and discardsblood sensor unit 44. The flow then shifts to step 275, removal of bloodsensor unit 44 is detected, and apparatus body 39 automatically turnsoff.

As described above, in measurement of the blood sugar level using bloodtest apparatus 31, laser emitting apparatus 33 is driven on conditions(conjunctive condition) that blood test apparatus 31 abuts on skin 13,and so laser light is not emitted for purposes other than puncturingskin 13 and is secure.

Further, prior to use of blood test apparatus 31, the user isauthenticated in step 261, so that it is also possible to allow only theauthorized party to operate the apparatus and prevent the unauthorizeduser to operate the apparatus, and so the apparatus is secure.

Blood test apparatus 31 automatically turns on and off, so that it ispossible to make the operation simple and reduce consumption of battery35.

Control of a Negative Pressure in Laser Emission

Blood test apparatus 31 of the present invention may intermittentlycreate a negative pressure more than once after puncturing. The timingof creating a negative pressure and its effect will be described withreference to FIG. 35 and FIG. 36.

When first skin contact sensor 62 detects skin 13, negative pressuremeans 34 starts being driven at time 166 a (step 156 in FIG. 33). Anegative pressure is created in negative pressure chamber 60, and skin13 is tensed and lifted as shown in state 167 a (step 157 in FIG. 33).Skin 13 is lifted and abuts on second skin contact sensor 110 m at time166 b (step 158 in FIG. 33). At time 166 b, skin 13 is as shown in state167 b in FIG. 36. Here, the negative pressure supplied to negativepressure chamber 60 is stopped (step 159 in FIG. 33). Then, at time 166c, skin 13 is punctured (step 160 in FIG. 33). Skin 13 becomes as shownin state 167 c, and blood 16 leaks.

Then, after the negative pressure supply is once stopped, a negativepressure is created again at time 166 d. By a negative pressure, theopening part of skin 13 widens as shown in state 167 d, so that blood 16flows out more easily (step 161 in FIG. 33).

In this way, one of the reasons for intermissively creating a negativepressure is to widen the hole punctured in skin 13 and collect blood 16more easily. Another reason is to prevent blood 16 from gushing out andbeing oversampled when suction is performed at a burst with strongnegative pressure. Therefore, negative pressure means 34 is operatedintermissively to such an extent that blood 16 does not overflow. Inthis way, power is saved by weakening sucking force, and an adequateamount of blood 16 is collected. When an adequate amount of blood 16 isobtained and accurate measurement is finished, blood test apparatus 31is removed from skin 13 (step 164 in FIG. 33). At time 166 e when themeasurement is finished, as shown in state 169 e, wound 168 widened by anegative pressure, of skin 13, is sealed again. Therefore, the woundheals faster.

As the case may be for some patients, blood 16 is less likely to flowingout from skin 13 even if skin 13 is punctured with laser light. In sucha case, it is also possible to make blood 16 flow out easily byincreasing the negative pressure after puncturing compared to thenegative pressure before puncturing. Since the maximum pressure(negative pressure) is fixed, a negative pressure is controlled bycontrolling the period valve 34 b is closed. Further, it is alsopossible to configure so as to create a negative pressure continuously,instead of creating a negative pressure intermissively.

Further, blood test apparatus 31 of the present invention may perform a“rubbing operation” before and after puncturing. The rubbing operationwill be described with reference to FIG. 37.

The rubbing operation is performed, for example, by driving pump 34 a(for example, an electric suction pump) at a constant voltage andopening and closing valve 34 b (for example, an electromagnetic valve)at a predetermined timing. In the operation example shown in FIG. 37,during the period (period 92) after first skin contact sensor 62 detectsskin 13 and negative pressure means 34 starts being driven (startssuction) until the skin is punctured with laser light, rubbing (rubbingfor preparation before puncturing) is performed as preparation beforepuncturing. After the skin is punctured with laser light, during theperiod (period 93) after guiding of blood 16 into detecting section 51of blood sensor 42 is detected (a drop of blood is detected) untilelectromagnetic valve 34 b is closed, rubbing (suction after puncturing)is performed at least once. In FIG. 37, air pressure level 90 is anegative pressure level (for example, −10 kPa) at which suction ishardly felt by patient, and level 91 is the maximum pressure (negativepressure) (for example, −70 kPa) when pump 34 a is driven at a constantvoltage. The opening and closing operations of valve (electromagneticvalve) 34 b that results in rubbing operation, is performed at a timingat which the air pressure in negative pressure chamber 60 changesbetween level 90 and level 91 and its change period is longer (forexample, 0.1 seconds or longer) than the minimum period skin 13 reactsto the change of the negative pressure. Such opening and closingoperations of valve (electromagnetic valve) 34 b are performed from whensuction is started until when a drop of blood is detected and theelectromagnetic valve is closed (electromagnetic valve opening andclosing operation period 94). As described above, the electromagneticvalve is closed after a drop of blood is detected, so that the puncturedhole in skin 13 is widened and blood 16 is collected more easily. Whenblood 16 is collected and measurement is finished, negative pressuremeans 34 stops being driven (i.e., suction by a pump is stopped and thevalve is released).

This rubbing operation improves blood circulation and makes blood 16flow out more easily. By rubbing skin 13, the part to be punctured isheated (which improves blood circulation), so that it is possible toincrease the amount of blood collected compared to a case skin 13 is notrubbed. Further, the rubbing operation alleviates the pain uponpuncturing.

The Laser Perforation Apparatus

Blood test apparatuses 31 and 31 a including the laser perforationapparatus of the present invention include a laser perforation apparatusshown in FIG. 38. This laser perforation apparatus has a same structureas blood test apparatuses 31 and 31 a without blood sensor unit 44 andmembers relating to blood sensor unit 44 (for example, connectorsconnected with blood sensor 42). This laser perforation apparatus has afunction of controlling the laser output of laser emitting apparatus 33so as to puncture the same position to be punctured in a divided mannerin one puncturing operation. Here, the “puncturing in a divided manner”refers to dividing one puncturing operation in space or in time. To bemore specific, the former refers to a case where the puncturingoperation is performed by dividing a laser light into a plurality ofoptical paths (branch control of the laser output), and the latterrefers to a case where the puncturing operation is performed by emittinga laser light several separate times (pulse control of the laseroutput).

Branch of Laser Light in Laser Emission

Blood test apparatuses 31 and 31 a of the present invention may punctureskin 13 by dividing one laser light emitted from laser emittingapparatus 33 into a plurality of laser lights. In FIG. 39, the referencenumeral “33” is the laser emitting apparatus, and “13” is the skin ofthe patient. Further, reference numerals “170 a,” “170 b” and “170 c”are splitters, each of which distributes incident light uniformly byallowing half of the incident light to pass through and reflecting theother half of the incident light. These splitters 170 a, 170 b and 170 care formed with half mirrors.

Reference numerals “171 a,” “171 b” and “171 c” show total reflectionmirrors that reflect all the incident light. These total reflectionmirrors (hereinafter simply “mirrors”) 171 a, 171 b and 171 c are pairedwith splitters 170 a, 170 b //ad 170 c, respectively. In FIG. 39, thesesplitters 170 a, 170 b and 170 c and mirrors 171 a, 171 b and 171 c areset at predetermined angles with respect to incident light so that thesame irradiated position 177 is punctured.

Laser light 172 emitted from laser emitting apparatus 33 is branchedinto laser light 173 a and 173 b by splitter 170 a. Branched laser light173 b enters mirror 171 a, and laser light 173 b is totally reflected bythis mirror 171 a and becomes laser light 174. This laser light 174 isbranched into laser light 175 a and laser light 175 b by splitter 170 b.Branched laser light 175 a directly punctures irradiated position 177 inskin 13. Further, laser light 175 b branched at splitter 170 b istotally reflected by mirror 171 b, becomes laser light 175 c andpunctures irradiated position 177 in skin 13.

On the other hand, laser light 173 a which passes through splitter 170 ais branched into laser light 176 a and laser light 176 b by splitter 170c. Branched laser light 176 a directly punctures irradiated position 177in skin 13. Further, laser light 176 b branched by splitter 170 c istotally reflected by mirror 171 c, becomes laser light 176 c andpunctures irradiated position 177 in skin 13.

In this way, one laser light 172 is branched into a plurality of opticalpaths and punctures irradiated position 177 in skin 13, and the skin ispunctured with laser light having a small output, so that it is possibleto alleviate the pain. Therefore, it is possible to focus laser lightson blood capillaries inside skin 13 and perform puncturing.

Further, as shown in FIG. 40, if mirror 171 c is arranged farther fromlaser light 176 a than the position shown in FIG. 39, it takes laserlight 176 b branched by splitter 170 c a longer time to be totallyreflected by mirror 171 c, become laser light 176 c and reach irradiatedposition 177 in skin 13. In this way, by arranging mirrors atappropriate positions, it is possible to control the laser output sothat the same position can be irradiated with a plurality of branchedlaser lights in order.

Cubic optical device 178 that divides a rectangular parallelepiped withdiagonal line 178 a as shown in FIG. 41 is preferably used as splitters170 a, 170 b and 170 c and mirrors 171 a, 171 b and 171 c. Each of cubicsplitters 170 a, 170 b and 170 c is formed by attaching mirrors ofdifferent refractive indexes together on a matching surface, and each ofcubic mirrors 171 a, 171 b and 171 c is formed by attaching together asurface that totally reflects light and a surface that totally transmitslight. In this way, optical device 178 formed in a cubic shape does notcause a shift of a transmitting optical path and ghost, and can maintainhigh accuracy against changes such as division and refraction of theoptical path. Further, one cubic optical device can constitute all oreach of splitters 170 a, 170 b and 170 c and mirrors 171 a, 171 b and171 c.

For example, a case will be described where laser branches shown in FIG.39 and FIG. 40 are configured with cubic optical devices. Althoughbranches of laser light 172 are shown in a two-dimensional image in FIG.39 and FIG. 40, if these are shown in three-dimensional image, the imagebecomes as shown in FIG. 42. As shown in FIG. 42A, laser light 172emitted from laser emitting apparatus 33 is once branched into aplurality of optical paths and focused on one irradiated position 177finally. FIG. 42B shows an example of a cube that realizes this branch.In cube 179 shown in FIG. 42B, splitters 170 a, 170 b and 170 c andmirrors 171 a, 171 b and 171 c are arranged at fixed predeterminedpositions. In this way, by accommodating splitters 170 a, 170 b and 170c and mirrors 171 a, 171 b and 171 c used for laser branch in cube 179,it is possible to make fine positioning unnecessary and emit laser lightwhich is controlled in blanches, to the desired position only byarranging cube 179 on a laser optical axis.

As the method of branching a laser light, a laser light maybe dividedusing an optical fiber. FIG. 63A and FIG. 63B show a method of branchinga laser light using an optical fiber. FIG. 63A shows a case where alaser light from laser emitting apparatus 33 is divided into twobranches by branch fiber cable 421. In this case, laser light 422 whichis divided into two branches is emitted from this two-branch fiber cable421 toward the same irradiated position 177 in skin 13. Two-branch fibercable 421 includes one optical fiber directional coupler 423. Further,FIG. 63B shows a case where a laser light from laser emitting apparatus33 is divided into four branches by branch fiber cable 424. In thiscase, laser light 425 divided into four branches is emitted from thisfour-branch fiber cable 424 toward irradiated position 177 in skin 13.Four-branch fiber cable 424 includes three optical fiber directionalcouplers 423. In this way, even if an optical fiber is used, as in thecase shown in FIG. 39, one laser light emitted from laser emittingapparatus 33 can be divided into a plurality of branches and punctureskin 13. Particularly, when a fiber cable is used, laser light does notleak outside, so that handling is much simpler than the case where asplitter is used.

FIG. 64 is a schematic view showing the configuration of optical fiberdirectional coupler 423. Generally, a directional coupler is an opticaldevice that branches a light. Optical fiber directional coupler 423 isconfigured by removing clads 428 of two optical fibers 426 at couplingsection 427 and making cores 429 closer to each other. When light entersfrom one optical fiber 426, in optical fiber directional coupler 423,the light transmits to the other core 429 near the part where two cores429 come close to each other by the interference effect of light, andthe light can be branched.

FIG. 65 shows a case where branch joint section 430 and fiber cable 431are used as a means for branching laser light using an optical fiber.Here, laser light 432 emitted from laser emitting apparatus 33 isdivided into two branches via branch joint section (T-branch) 430.Branch joint section 430, for example, incorporates triangular totalreflection mirror 433 and branches laser light 432 in an inverted Tshape. The branched laser lights puncture the same position 177 in skin13 to be irradiated via fiber cable 431.

Generally, when skin 13 is irradiated with laser light, the irradiatedpart absorbs the light and its temperature thereby increases rapidly.This increase in the temperature evaporates blood 16 and lifts skin 13in a balloon shape. When skin 13 is further lifted, skin 13 is destroyedand blood 16 flows out. After blood 16 flows out, the bottom surfacepunctured with laser light is carbonized, and a carbonized odor isproduced. The carbonized odor may be deodorized with a deodorizer.

This laser emitting apparatus 33 is designed so that laser lightpunctures skin 13 of the patient approximately 0.5 mm deep.

In this case, the type the laser light by laser emitting apparatus 33may be Er:YAG or CO₂ gas, the wavelength range may be 2.7 to 3.5 μm or6.5 to 10.5 μm, the pulse width may be 50 to 400 μs, preferably 200 μs,and the output may be 300 mJ to 3000 mJ. Further, the diameter of a shotmay be 0.1 mm to 0.5 mm, and the depth of a shot maybe 0.3 to 0.7 mm.Further, the charge voltage falls in a range of 200 to 700 V, preferably500 V. This high voltage is obtained by charging electrical charge in acapacitor using a battery and discharging this electrical charge at aburst.

The Emission Angle in Laser Emission

One laser light may be emitted from an oblique direction with respect toskin 13 and puncture skin 13. In FIG. 43, a negative pressure is createdin negative pressure chamber 60 of blood sensor unit 44 by negativepressure means 34, and skin 13 is lifted. Laser light 181 is emitted atan angle less than 90 degrees with respect to the direction of thetangent to top 180 of the lift of skin 13. In this way, when laser lightis emitted at an angle less than 90 degrees with respect to thedirection of the tangent to the top of the lifted skin, compared to acase where laser light is emitted from a vertical direction, laser light181 is emitted from an oblique direction with respect to a surface whereblood capillaries are crowded. Therefore, although the emissionintensity per unit area of laser light 181 decreases, laser light 181 ismore likely to damage the blood capillaries. Therefore, blood collectionefficiency improves. Accordingly, even when the depth of puncturing isshallow, blood 16 can be collected enough, and the pain of the patientis alleviated.

Further, the shape of emission of laser light 181 does not have to beround, and, as shown in FIG. 44, may be ellipse 183 or rectangle 184.When the shape of emission is made ellipse 183 or rectangle 184, laserlight 181 is more likely to damage the crowded blood capillaries, andblood collection efficiency improves. Therefore, blood 16 can becollected enough even with a shallow depth of puncturing, and so thepain of the patient can be alleviated.

In blood test apparatuses 31 and 31 a of the present invention, thelaser output intensity can be made variable even with one laser emittingapparatus 33.

As shown in FIG. 45, a plurality of types of filters that transmitdifferent amounts of light, for example, plate 193 to which neutraldensity (ND) filters 191 a to 191 d are attached, may be providedbetween laser emitting apparatus 33 and skin 13. Plate 193 is arrangedin the emission path of laser light 194. By rotating plate 193, theamount of laser light 194 emitted on skin 13 is controlled. Bycontrolling the amount of laser light, the depth of puncturing can becontrolled.

By this means, in addition to the conventional method which has beenperformed to control laser intensity, of controlling the applied voltagein a case of a flashlamp and controlling the current in a case ofsemiconductor laser, the output of laser puncturing can be adjustedusing an ND filter. Therefore, the laser output can be controlled inmore detail.

Further, in another application, when laser output intensity isdetermined by the voltage applied to the flashlamp, making the voltagevariable may cause deterioration of the stability of the voltage valueand fluctuation of laser output. To solve this problem, by a fixedvoltage and using ND filters 191 a to 191 d that transmit differentamount of light even when the output of laser light 194 decreases(changes), it is possible to maintain the output of the laser lightconstant. Therefore, it is possible to provide stable laser output.

Pulse Control (Time Division) in Laser Emission

To alleviate the pain upon puncturing, the skin may be punctured aplurality of times up to a certain depth. Compared to the method ofpuncturing the skin once using a large pulse with approximately 320 V asa charge voltage, as shown in FIG. 46, laser light is divided into threepulses 198 a, 198 b and 198 c, and the skin is punctured a plurality oftimes using these small pulses with approximately 210 V at intervals(i.e., intermission periods) of 100 μs to 1 msec. By this means, asshown in FIG. 47, skin 13 can be punctured in three stages of level 199a, 199 b and 199 c that match pulses 198 a, 198 b and 198 c,respectively. In this case, a capacitor is charged in intermissionperiods of 100 μs to 1 msec and a high voltage is obtained.

According to the control by this puncturing method, the depth skin 13 ispunctured with one pulse is shallow, so that it is possible to alleviatethe pain and puncture the skin to a predetermined depth. In this case,it is important to make intervals between pulses 198 a, 198 b and 198 cshort, between 100 μs and 1 msec, and the next puncturing is preferablyperformed before blood 16 leaks.

Further, to alleviate a pain upon puncturing, as another method forpuncturing the skin to a predetermined depth a plurality of times, amethod of making laser light variable on a continuous basis andperforming fractionated emission, will be described. The part to bepunctured with the present invention is, for example, the skin of thefinger cushion. The skin is formed, in order from the surface, with theepidermis that has the stratum corneum outside and the dermis where painpoints and blood capillaries exist. Therefore, by providing energy thatremoves only the epidermis by the first emission or by a plurality ofemissions and then puncturing the dermis with little energy, the pain isalleviated.

For example, when laser rod (laser crystal) 33 d which is formed withEr:YAG doped with erbium and which is φ2.5 mm and 52 mm long, is used, alarge pulse of approximately 450 V is used as the charge voltage toflashlamp (excitation light source) 33 e in one puncturing. FIG. 48Ashows the circuit for causing the operation at this time, FIG. 48B showsthe current inputted to flashlamp 33 e, and FIG. 48C shows the output ofthe laser light.

In the circuit diagram of FIG. 48A, when thyristor (SCR 1) 401 is turnedon, a boosted voltage of several kV, is outputted from trigger coil 402,the xenon gas filling flashlamp 33 e is ionized, main discharge ofelectrolytic capacitor 403 is started, and flashlamp 33 e emits light.By this emission of light from flashlamp 33 e, laser rod 33 d isexcited, and laser light is emitted. The reference numeral “404” isresistance (R1).

In the above-described case, the skin is punctured in one time.

Next, a case will be described where laser light is divided and emittedin several times with one charging of the electrolytic capacitor. FIG.49A, FIG. 49B and FIG. 49C show the circuit diagram, the currentinputted to flashlamp 33 e and the output of laser light at this time,respectively.

Referring to the circuit diagram of FIG. 49A, in a case where lightemitted by flashlamp 33 e is divided in several times, when a “high”signal is inputted to transistor (IGBT) 411 with a large current andhigh switching speed, the negative terminal of flashlamp 33 e isgrounded when transistor (IGBT) 411 is turned on, a voltage fromelectrolytic capacitor 412 is applied to flashlamp 33 e, and, at thesame time, a boosted voltage of several kV is outputted from triggercoil 413. By this means, the xenon gas filling flashlamp 33 e isionized, main discharge of electrolytic capacitor 412 is started, andflashlamp 33 e emits light. Next, when a “low” signal is inputted totransistor (IGBT) 411, transistor (IGBT) 411 is turned off, and thevoltage stops being applied to flashlamp 33 e. By this means, flashlamp33 e stops emitting light and stops outputting laser light. By repeatingthis operation, it is possible to divide laser output into severaltimes. Here, a case has been described where laser light is outputted intwo outputs. The reference numeral “414” is resistance (R1).

As is clear from FIG. 49C, laser light can be emitted with high power atfirst and then emitted with low power. When laser rod 33 d of Er:YAGwith φ2.5 mm and 52 mm long described in the present example is used,the minimum voltage of flashlamp 33 e for emitting laser light is 370 V,and so it is necessary to set the first voltage higher than 370 V and toshorten the emission time of flashlamp 33 e in order to reduce totalenergy. The second voltage applied to flashlamp 33 e is set a lowvoltage of 370 V. By this means, it is possible to puncture skin 13 intwo stages, levels 199 a and 199 b (see FIG. 47).

According to the control using this puncturing method, first, theepidermis of skin 13 is removed, and, then, the dermis is punctured withlittle energy, and so laser light does not reach the deep partunderneath the dermis, so that it is possible to alleviate the pain andpuncture the skin to a predetermined depth. The epidermis is puncturedso that blood 16 does not leak.

Power Supply Control

The blood test apparatus of the present invention has a laser emittingapparatus that consumes a large amount of power, and so management of apower supply is important. In a case of a portable device that uses abattery as a power supply, the capacity is limited, and so management ofa power supply is particularly important.

Further, when the apparatus influences safety of life, for example, anapparatus that measures the blood sugar level, cases must be avoidedwhere measurement cannot be performed due to power exhaustion, and it isimportant that a blood test (for example, measurement of the blood sugarlevel) can be conducted at least.

The blood test apparatus of the present invention preferably has a powersupply control circuit that controls a power supply for driving thelaser emitting apparatus included in the apparatus and a power supplyfor driving the electrical circuit section. Further, the power supplycontrol circuit preferably controls the power supply for driving thelaser emitting apparatus and the power supply for driving the electricalcircuit section separately.

“Controlling separately” means determining whether or not to supplypower for driving the laser emitting apparatus and power for driving theelectrical circuit section according to the power supply (particularly,battery) level and the voltage, and determining from which of powersupply, power is supplied.

The power supply in the blood test apparatus of the present inventionpreferably has a battery power supply, so that the blood test apparatuscan be used as a portable device. There maybe one battery power supplyor two or more battery power supplies.

A battery may be a secondary battery or a primary battery, or acombination of both batteries. Examples of the secondary battery includea lithium-ion battery, lithium polymer battery and nickel hydridebattery. Examples of the primary battery include a lithium battery,manganese cell, alkali cell and oxyride dry-cell battery.

The power supply of the blood test apparatus of the present inventionmay have a connection terminal for an emergency power supply, inaddition to a battery power supply, so that the blood test apparatus isconnected to other power supplies and used when the battery of thebattery power supply is consumed. Examples of the emergency power supplyinclude a dry cell which is easily available, a USB terminal which isused in, for example, personal computers, a fuel cell and a hand dynamo.These power supplies can be connected in a simple manner.

Further, the power supply of the blood test apparatus of the presentinvention may have an external power supply in addition to a batterypower supply. When the apparatus is connected to an external powersupply, preferably, the external power supply is used preferentially,and electrical power from a battery is stopped or the battery ischarged.

The blood test apparatus may have a battery level measuring circuit formeasuring the battery level of a battery power supply. Further, theblood test apparatus preferably has a comparing section that comparesthe battery level measured by the battery level measuring circuit with apredetermined value (e.g., electrical levels), so that the battery levelis learned and whether or not it is possible to perform laser puncturingor a test is determined.

As described above, the comparing section stores predeterminedelectrical levels. The first of the predetermined electrical level isthe electrical level required for the predetermined number of times oftests (including the laser puncturing and measurement). This value isreferred to as the first battery level threshold. When the battery levelis lower than the first battery level threshold, a warning (batterylevel warning) is preferably issued to encourage the user to change thebattery. The first battery level threshold may be set as appropriateaccording to designed circuits and is basically a fixed value.

The second of the predetermined electrical level is the electrical levelrequired for one test (including the puncturing and measurement). Thisvalue is referred to as the second battery level threshold. When thebattery level is equal to or higher than the second battery levelthreshold, the apparatus determines that at least one test can beperformed, and conducts a test. As described above, when the batterylevel is lower than the first battery level threshold, a battery levelwarning is preferably issued.

On the other hand, when the measured battery level is lower than thesecond battery level threshold, a normal test cannot be performed, andso, preferably, laser puncturing is not allowed, and the user isinformed that a test cannot be performed (a message of unavailability).However, there is a case where, although laser puncturing is notpossible, measurement process which consumes small power can beperformed. Therefore, it is possible to perform measurement afterperforming puncturing using means other than laser light.

The second battery level threshold is preferably set based on thebattery power consumption consumed in the previous test. To be morespecific, the second battery level threshold is preferably a sum of thebattery power consumption and the electrical level required to drive theelectrical circuit for measurement. The battery power consumptionchanges according to a change of laser output setting of the laseremitting apparatus, and so the latest data of the battery powerconsumption consumed in the test is stored. In this way, the secondbattery level threshold is variable.

The third of the predetermined electrical level is a sum of theelectrical level required to charge the laser emitting apparatus onceand the electrical level required to drive the electrical circuit formeasurement. This value is referred to as the third battery levelthreshold. When the power supply for charging the laser emittingapparatus and the power supply for driving the electrical circuit aredifferent, the third battery level threshold is used as a criterion fordetermining whether or not an emergency power supply for driving theelectrical circuit is used to charge the laser emitting apparatus. Theelectrical level required to charge the laser emitting apparatus once isdetermined according to the capacity of the capacitor that is chargedfor laser excitation, the charge current and the internal resistance ofthe battery.

Setting of a Charge Current Value According to the Battery Level

Further, the charge level for charging the laser emitting apparatus maybe set based on the battery level measured in the battery levelmeasuring circuit. FIG. 61A to FIG. 61C show examples of setting thecharge level based on the battery level.

FIG. 61A shows a method of changing the charge current stepwiseaccording to the ratio of the battery level (Y axis). For example, whenthe battery level is 75 to 100% (first zone), the charge current valueis made a maximum value (100%), when the battery level is 50 to 75%(second zone), the charge current value is made 50% of the maximumvalue, and, when the battery level is 25 to 50% (third zone), the chargecurrent is made 25%.

FIG. 61B shows a method of changing the charge current (X axis)continuously in proportion to the battery level (Y axis).

FIG. 61C shows a method of changing the charge current (X axis)continuously based on a change curve of the ratio of the battery level(Y axis) so that a curve becomes a variable curve which is an inverse ofthe change curve. FIG. 61C shows the control performed in accordancewith a curve symmetric about the proportional line of “Y═X+a (a:offset).”

The blood test apparatus of the present invention preferably has abattery voltage measuring circuit for measuring the battery voltage ofthe battery power supply. Further, the blood test apparatus preferablyhas a comparing section that compares the battery voltage measured bythe battery voltage measuring circuit with a predetermined voltagevalue.

Cases occur where, even if the electrical level required for a test(puncturing and measurement) remains in the battery, when the laseremitting apparatus is charged for laser puncturing, the battery voltagebecomes lower than the voltage required to drive the electrical circuitsection for measurement. Therefore, cases occur where, although there isenough battery level for measurement, measurement cannot be performed.Therefore, the battery voltage measuring circuit checks whether or notthe battery outputs a sufficient voltage.

As described above, the comparing section stores predetermined voltagevalues. The first predetermined voltage value is preferably higherenough than the minimum voltage required to drive the electrical circuitsection for measurement. This voltage value is referred to as the firstvoltage threshold. The first voltage threshold is set so that, even if abattery voltage decreases by charging the laser emitting apparatus, thebattery voltage is not lower than the minimum required voltage. How muchthe battery voltage decreases by the charging depends on the property ofthe battery, and so the first voltage threshold is set as appropriateaccording to the property of the battery.

When the comparing section determines that the battery voltage measuredby the battery voltage measuring circuit before the laser emittingapparatus is charged, is lower than the first voltage threshold, thelaser emitting apparatus is preferably charged with a lower current thanthe normal current, because the battery voltage is less likely todecrease when the laser emitting apparatus is charged with a lowercurrent.

FIG. 62 shows the relationship between the battery voltage (Y axis) andthe battery level (X axis) when the charge level is changed. Curve 410,curve 420 and curve 430 show the relationship between the batteryvoltage (Y axis) and the battery level (X axis), when the charge currentis 0 (no load), when the charge current is I, and when the chargecurrent is I′ (>I), respectively. Curve 420 and curve 430 show that thebattery voltages are lower than curve 410. This is caused by theresistance (421 and 431) inside the battery.

When the voltage level required to drive the electrical circuit formeasurement is set 440, in a case where the charge current is I (curve420), the battery can drive the electrical circuit until the batterylevel is X2. On the other hand, when the charge current is I′ (>1)(curve 430), the battery can no longer drive the electrical circuit oncethe battery level is X1. In this way, when the charge current islowered, a decrease of the battery voltage is controlled. Significantdecrease of the battery voltage is not preferable, because batteryenergy which cannot be used increases as shown by 450.

The second voltage value determined in advance in the comparing sectionis equal to or higher than the first voltage threshold and has primarilya sufficient margin. This voltage value is referred to as the secondvoltage threshold. For example, the first voltage threshold isapproximately +0.5 to 1 V.

When the comparing section determines that the battery voltage measuredby the battery voltage measuring circuit before the laser emittingapparatus is charged, is higher than the second voltage threshold, thelaser emitting apparatus is preferably charged with a higher chargecurrent.

The blood test apparatus of the present invention has a display section(see FIG. 1) that displays the test result of a blood test. Theabove-described messages for battery level warning and unavailabilityare preferably displayed on the display section.

A first example of a power supply controlling section

FIG. 50 shows a first example of power supply controlling section 200-1of the blood test apparatus.

In FIG. 50, outlet 201 connected to a household AC power (used as anexample of an external power supply) is connected to AC adapter 202. Theoutput of AC adapter 202 can be connected to one input of power supplycontrolling circuit 203 removably, using a connector.

Battery 210 is connected to battery level and battery voltage measuringcircuit 212. The first output of circuit 212 is connected to powersupply controlling circuit 203, and the second output of circuit 212 isconnected to comparing section 211.

Connection terminal 204 for an emergency power supply is connected topower supply control circuit 203.

When power supply control circuit 203 is connected to AC adapter 202,power supply control circuit 203 controls so that the power supply of ACadapter 202 is preferentially used and battery 210 is not used. When thevoltage outputted from AC adapter 202 is detected, and, if this voltageis outputted, supply from battery 35 is stopped forcibly or battery 210is charged.

The first output of power supply control circuit 203 is connected toelectrical circuit section 36 a. The second output of power supplycontrol circuit 203 is connected to the input of boost circuit 205, andthe output of boost circuit 205 is connected to laser emitting apparatus33.

The first output of comparing section 211 is connected to power supplycontrol circuit 203. The second output of comparing section 211 isconnected to boost controlling section 208, and the output of boostcontrolling section 208 is connected to boost circuit 205. The thirdoutput of comparing section 211 is connected to display controllingsection 209, and the output of display controlling section 209 isconnected to display section 37.

Puncture button 75 is connected to the input of electrical circuitsection 36 a, and the signal caused by pressing puncture button 75 isconnected to the input of boost controlling section 208 via electricalcircuit section 36 a. Emergency button 207 is connected to the otherinput of boost controlling section 208. The output of electrical circuitsection 36 a is connected to display section 37.

A first example of the operation of power supply controlling section200-1 shown in FIG. 50 will be described with reference to FIG. 51. Instep 311, power supply is started. The flow shifts to step 312, and thebattery level is measured. In step 313, the measured battery level iscompared with the first battery level threshold, and, in step 314, thebattery level is compared with the second battery level threshold. Thefirst battery level threshold refers to the electrical level requiredfor the predetermined number of times of tests (including the laserpuncturing and measurement), and the second battery level thresholdrefers to the electrical level required for one test (including thepuncturing and measurement).

When the battery level is determined to be equal to or higher than thefirst battery level threshold in step 313, the flow shifts to step 318,and the laser emitting apparatus is charged.

When the battery level is determined to be lower than the first batterylevel threshold in step 313 and determined to be equal to or higher thanthe second battery level threshold in step 314, a battery level warningis displayed in step 315 to encourage the user to change the battery,and onto step 318, the laser emitting apparatus is charged.

When the battery level is determined to be lower than the first batterylevel threshold in step 313 and determined to be lower than the secondbattery level threshold in step 314, a message of unavailability isdisplayed on the display section in step 316 to inform the user that anormal test cannot be performed, and power supply to the laser emittingapparatus is not allowed in step 317.

When the laser emitting apparatus is charged to a predetermined level,laser light is emitted in step 319 and the skin is punctured. Thecomponents in blood flowing out from the skin punctured in step 321 aremeasured, the obtained measurement result is displayed, and then theblood test is finished.

After the test, the battery level is measured in step 322. In step 323,the difference between the battery level measured in step 312 and thebattery level measured in step 322, and the battery consumption of thistime are calculated. Further, in step 323, a sum of the batteryconsumption of this time and the minimum electrical level required todrive the electrical circuit section is calculated, and the secondbattery level threshold is set again. In step 324, the power supply isstopped.

A second example of the operation of power supply controlling section200-1 shown in FIG. 50 will be described with reference to FIG. 52. Instep 311, the power supply is started. In step 331, the battery voltageis measured, and, in step 332, the battery level is measured.

In step 333, the difference between the voltage measured in step 331 andthe voltage drop value calculated in step 347 (described later) in theprevious test, is calculated. Further, in step 333, the difference iscompared with the minimum voltage required to drive the electricalcircuit section.

In step 313, the battery level measured in step 332 is compared with thefirst battery level threshold, and, in step 314, the battery levelmeasured in step 332 is compared with the second battery levelthreshold. As described above, the first battery level threshold refersto the electrical level required for the predetermined number of timesof tests (including the laser puncturing and measurement), and thesecond battery level threshold refers to the electrical level requiredfor one test (including the puncturing and measurement).

When the difference is determined to be equal to or higher than theminimum required voltage in step 333 and the battery level is determinedto be equal to or higher than the first battery level threshold in step313, the flow shifts to step 341, and the laser emitting apparatus ischarged with a normal current.

When the difference is determined to be equal to or higher than theminimum required voltage in step 333 and the battery level is determinedto be lower than the first battery level threshold in step 313, abattery level warning is displayed in step 315 to encourage the user tochange the battery, the flow shifts to step 341, and the laser emittingapparatus is charged with a normal current.

When the difference is determined to be equal to or higher than theminimum required voltage in step 333 and the battery level is determinedto be lower than the first battery level threshold in step 313 anddetermined to be lower than the second battery level threshold in step314, a message that the apparatus cannot be used is displayed in step316 to inform the user that a normal test cannot be performed, and powersupply to the laser emitting apparatus is not allowed in step 317.

On the other hand, if the difference is determined to be lower than theminimum required voltage in step 333, the flow shifts to step 335, amessage that normal charge cannot be performed is displayed to informthe user that the laser emitting apparatus cannot be charged normally(for example, the charging duration becomes long), and the user isrequested to press an emergency button when a test is performed, in step336.

When the emergency button is not pressed in step 336, the flow shifts tostep 317, and power supply to the laser emitting apparatus is notallowed.

When the emergency button is pressed in step 336, the laser emittingapparatus is charged with a lower current than usual in step 337. Thecurrent value control for the charging takes place in boost controllingsection 208. In step 338, the laser emitting apparatus emits laser lightand punctures the skin, and, in step 339, measures the components inblood flowing out from the skin punctured in step 339 and displays themeasurement result. After the test, the power supply is stopped in step348.

On the other hand, when the laser emitting apparatus is charged with anormal current in step 341, the voltage of the battery being charged ismeasured in step 342. In step 343, the charged laser emitting apparatusemits laser light and punctures the skin. In step 344, the components inblood flowing out from the punctured skin is measured, and themeasurement result is displayed. In step 345, the battery level afterthe measurement is measured.

In step 346, the difference between the battery level measured in step332 and the battery level measured instep 345 is calculated and made thebattery consumption of this time. Further, in step 346, a sum of thebattery consumption of this time and the minimum electrical levelrequired to drive the electrical circuit section for measurement, iscalculated, and the second battery level threshold is set again.

Further, instep 347, the difference between the voltage measured in step331 and the voltage measured in step 342 is calculated and made thevoltage drop value. The voltage drop value is used in step 333(described above) in the next test. Then, the power supply is stopped instep 348.

A third example of the operation of power supply controlling section200-1 shown in FIG. 50 will be described with reference to FIG. 53. Instep 311, power supply is started. The flow shifts to step 312, wherethe battery level is measured. In step 313, the measured battery levelis compared with the first battery level threshold, and, in step 314,the measured battery level is compared with the second battery levelthreshold.

As described above, the first battery level threshold refers to theelectrical level required for the predetermined number of times of tests(including the laser puncturing and measurement), and the second batterylevel threshold refers to the electrical level required for one test(including the puncturing and measurement).

When the battery level is determined to be equal to or higher than thefirst battery level threshold in step 313, the flow shifts to step 351,and the charge current value (see step 358 described later) for chargingthe laser emitting apparatus in the previous test is set as the chargecurrent value in the present test.

When the battery level is determined to be lower than the first batterylevel threshold in step 313 and determined to be equal to or higher thanthe second battery level threshold in step 314, a battery level warningis displayed in step 315 to encourage the user to change the battery,the flow shifts to step 351, and the charge current value (see step 358)for charging the laser emitting apparatus in the previous test is set asthe charge current value in the present test.

When the battery level is determined to be lower than the first batterylevel threshold in step 313 and determined to be lower than the secondbattery level threshold in step 314, a message of unavailability isdisplayed to inform the user that a test cannot be performed in step316, and power supply to the laser emitting apparatus is not allowed instep 317.

In step 352, the laser emitting apparatus is charged with the chargecurrent value set in step 351. When the battery is changed or the typeof the power supply is changed, the laser emitting apparatus is chargedwith a predetermined charge current value. In step 353, the voltage ofthe battery being charged is measured. Instep 354, the voltage of thebattery being charged is compared with the first voltage threshold. Instep 356, the voltage of the battery being charged is compared with thesecond voltage threshold.

As described above, the first voltage threshold is higher enough thanthe minimum voltage required to drive the electrical circuit section formeasurement, and the second voltage threshold primarily has a sufficientmargin. This voltage value is referred to as the second voltagethreshold. For example, the second voltage threshold is higher than thefirst voltage threshold by approximately +0.5 to 1 V.

When the voltage of the battery being charged is equal to or higher thanthe first voltage threshold in step 354 and determined to be equal to orlower than the second voltage threshold in step 356, the charge currentvalue at this time is stored as the charge current value in the nexttest (used in step 351 of the next test) in step 358.

When the voltage of the battery being charged is determined to be lowerthan the first voltage threshold in step 354, the charge current valueis lowered in step 355. On the other hand, when the voltage of thebattery being charged is determined to exceed the second voltagethreshold in step 356, the charge current is increased in step 357.

In step 359, the laser emitting apparatus emits laser light andpunctures the skin. In step 361, the components in blood flowing outfrom the punctured skin is measured, and the measurement result isdisplayed. In step 362, the battery level after the test is measured. Instep 363, the difference between the battery level measured in step 312and the battery level measured in step 362 is calculated and made thebattery consumption level of this time. Further, in step 363, a sum ofthe battery consumption of this time and the minimum electrical levelrequired to drive the electrical circuit section for measurement, iscalculated and reset as the second battery level threshold. In step 364,the power supply is stopped.

A fourth example of the operation of power supply controlling section200-1 shown in FIG. 50 will be described with reference to FIG. 54.Although the flow shown in FIG. 54 is similar to the flow shown in FIG.53 but is different in the method of setting the charge current valuefor charging the laser emitting apparatus. That is, in the flow shown inFIG. 54, the charge current value is set in step 350 based on thebattery level. The specific setting method is as described above, and,basically, when the ratio of the battery level is higher, the apparatusis charged with a higher current value.

The other steps are the same as those in the flow shown in FIG. 53.

A second example of the power supply controlling section will bedescribed.

FIG. 55 shows a second example of power supply controlling section 200-2of the blood test apparatus.

In FIG. 55, outlet 201 connected to a household AC power (used as anexample of the external power supply) is connected to AC adapter 202.The output of AC adapter 202 can be connected to one input of powersupply control circuit 203 removably, using a connector.

Battery 210 a is connected to battery level and battery voltagemeasuring circuit 212. The first output of circuit 212 is connected topower supply control circuit 203, and the second output of circuit 212is connected to comparing section 211. Battery 210 b is connected toelectrical circuit section 36 a. Connection terminal 204 for anemergency power supply is connected to power supply control circuit 203.

When power supply control circuit 203 is connected to AC adapter 202,power supply control circuit 203 controls so that the power supply of ACadapter 202 is preferentially used and battery 210 a is not used. Whenthe voltage outputted from AC adapter 202 is detected, and, if thisvoltage is outputted, supply from battery 35 is stopped forcibly orbattery 210 a is charged.

The output of power supply control circuit 203 is connected to boostcircuit 205, and the output of boost circuit 205 is connected to laseremitting apparatus 33.

The first output of comparing section 211 is connected to power supplycontrol circuit 203. The second output of comparing section 211 isconnected to boost controlling section 208, and the output of boostcontrolling section 208 is connected to boost circuit 205. The thirdoutput of comparing section 211 is connected to display controllingsection 209, and the output of display controlling section 209 isconnected to display section 37.

Puncture button 75 is connected to the input of electrical circuitsection 36 a, and the signal caused by pressing puncture button 75 isconnected to the input of boost controlling section 208 via electricalcircuit section 36 a. Emergency button 207 is connected to the otherinput of boost controlling section 208. The other output of electricalcircuit section 36 a is connected to display section 37.

A first example of the operation of power supply controlling section200-1 shown in FIG. 55 will be described with reference to FIG. 56. Theflow shown in

FIG. 56 is similar to the flow shown in FIG. 51. However, power supplycontrolling section 200-2 has two batteries (210 a and 210 b), and onlybattery 210 a (laser battery) is used to charge the laser emittingapparatus. Therefore, the battery level of the laser battery is measuredin step 312′, the battery level measured in step 312′ is compared withthe first battery level threshold in step 313′, and the battery levelmeasured in step 312′ is compared with the second battery levelthreshold in step 314′.

The other steps are the same as in the flow shown in FIG. 51.

A second example of the operation of power supply controlling section200-1 shown in FIG. 55 will be described with reference to FIG. 57.Although the flow shown in FIG. 57 is similar to the flow shown in FIG.56, the flow is different in the method of setting the charge currentvalue for charging the laser emitting apparatus. That is, in the flowshown in FIG. 57, the charge current value is set in step 350 based onthe battery level.

Although the details of the setting method are described above,basically, when the ratio of the battery level is higher, the apparatusis charged with a higher current value.

The other steps are the same as those in the flow shown in FIG. 56.

A third example of the power supply controlling section will bedescribed.

FIG. 58 shows a third example of power supply controlling section 200-2of the blood test apparatus.

In FIG. 58, outlet 201 connected to a household AC power (used as anexample of the external power supply) is connected to AC adapter 202.The output of AC adapter 202 can be connected to one input of powersupply control circuit 203 removably, using a connector.

Battery 210 a is connected to battery level and battery voltagemeasuring circuit 212 a. The first output of circuit 212 a is connectedto power supply control circuit 203, and the second output of circuit212 a is connected to comparing section 211. Battery 210 b is connectedto battery level and battery voltage measuring circuit 212 b. The firstoutput of circuit 212 b is connected to power supply control circuit203, and the second output of circuit 212 b is connected to comparingsection 211. Connection terminal 204 for an emergency power supply isconnected to power supply control circuit 203.

Both battery 212 a and battery 212 b are connected to power supplycontrolling section 203, and so battery 212 a and battery 212 b are usedto charge laser emitting apparatus 33 and drive electrical circuitsection 36 a. Normally, battery 212 a charges the laser emittingapparatus, and battery 212 b drives electrical circuit section 36 a.However, when the battery level of battery 212 a is low and the laseremitting apparatus cannot be charged and the battery level of battery212 b is sufficient, battery 212 b charges the laser emitting apparatusas a means for emergency.

When power supply control circuit 203 is connected to AC adapter 202,power supply control circuit 203 controls so that the power supply of ACadapter 202 is preferentially used and battery 210 a and battery 210 bare not used. When the voltage outputted from AC adapter 202 isdetected, and, if this voltage is outputted, supply from battery 210 aand battery 210 b is stopped forcibly or battery 210 a and battery 210 bare charged.

The first output of power supply control circuit 203 is connected toelectrical circuit section 36 a. The second output of power supplycontrol circuit 203 is connected to the input of boost circuit 205, andthe output of boost circuit 205 is connected to laser emitting apparatus33.

The first output of comparing section 211 is connected to power supplycontrol circuit 203. The second output of comparing section 211 isconnected to boost controlling section 208, and the output of boostcontrolling section 208 is connected to boost circuit 205. The thirdoutput of comparing section 211 is connected to display controllingsection 209, and the output of display controlling section 209 isconnected to display section 37.

Puncture button 75 is connected to the input of electrical circuitsection 36 a, and the signal caused by pressing puncture button 75 isconnected to the input of boost controlling section 208 via electricalcircuit section 36 a. Emergency button 207 is connected to the otherinput of boost controlling section 208. The output of electrical circuitsection 36 a is connected to display section 37.

A first example of the operation of power supply controlling section200-1 shown in FIG. 58 will be described with reference to FIG. 59.

The flow shown in FIG. 59 is similar to the flow shown in FIG. 56.However, power supply controlling section 200-3 has two batteries (210 aand 210 b), and both batteries are connected to power supply controlcircuit 203. Basically, battery 210 a (laser battery) is used to chargethe laser emitting apparatus, and battery 210 b (system battery) is usedto drive electrical circuit section 36 a. However, there is a casewhere, in an emergency, for example, when the battery level of battery210 a is low, battery 210 b is used to charge the laser emittingapparatus.

In the same way as in the flow shown in FIG. 56, the battery level ofthe laser battery is compared with the second battery level threshold instep 314′, and, when the battery level of the laser battery isdetermined to be lower than the second battery level threshold, amessage for informing the user that the laser battery cannot be used isdisplayed in step 371.

In step 372, the battery level of the system battery is measured. Instep 373, the battery level measured in step 372 is compared with thethird battery level threshold. The third battery level threshold may bea sum of the electrical level to be charged so as to enable the laseremitting apparatus to emit laser light and the minimum electrical levelof the system.

When the battery level of the system battery is determined to be lowerthan the third battery level threshold, a message that the apparatuscannot be used is displayed in step 316 to inform the user that the testcannot be performed. Further, in step 317, power supply to the laseremitting apparatus is not allowed.

On the other hand, when the battery level of the system battery isdetermined to be equal to or higher than the third battery levelthreshold in step 373, in step 374, a message that normal charge cannotbe performed is displayed to inform the user that the laser emittingapparatus cannot be charged normally (for example, the charging durationbecomes long), and, if the user still desires to perform a test, theuser is requested to press the emergency button.

When the emergency button is not pressed in step 375, the flow shifts to317, and power supply to the laser emitting apparatus is not allowed.

On the other hand, when the emergency button is pressed in step 375, thecharging of the laser emitting apparatus using the system battery isallowed in step 376, and the laser emitting apparatus is charged in step377. Charging in step 377 is preferably performed with a lower currentthan usual to avoid a voltage drop of the system battery. A currentvalue for charging is controlled by boost controlling section 208.

In step 378, the laser emitting apparatus emits laser light andpunctures the skin. In step 379, the components of blood flowing outfrom the punctured skin is measured, and the measurement result isdisplayed. Instep 381, a battery change warning for the system batteryis displayed to encourage the user to change the system battery. In step382, the power supply is stopped.

A second example of the operation of power supply controlling section200-3 shown in FIG. 58 will be described with reference to FIG. 60.Although the flow shown in FIG. 60 is similar to the flow shown in FIG.59, the flow is different in the method of setting the charge currentvalue for charging the laser emitting apparatus. That is, in the flowshown in FIG. 60, the charge current value is set in step 350 based onthe battery level. The specific setting method is as described above,and, basically, when the ratio of the battery level is higher, theapparatus is charged with a higher current value.

The other steps are the same as those in the flow shown in FIG. 59.

The disclosures of Japanese Patent Application No.2006-078418, filed onMar. 22, 2006, Japanese Patent Application No.2006-078419, filed on Mar.22, 2006, Japanese Patent Application No.2006-078420, filed on Mar. 22,2006, and Japanese Patent Application No.2006-078427, filed on Mar. 22,2006, including the specifications, drawings and abstracts areincorporated herein by reference in their entirety.

INDUSTRIAL APPLICABILITY

The blood test apparatus and its control method of the present inventionare suitable for use as a blood test apparatus and its control methodthat can collect a small amount of blood required and enough formeasurement in a reliable manner and perform reliable measurementwithout placing a load on the patient with a simple configuration.Therefore, the present invention is widely applicable to, for example,household medical equipment particularly used by diabetes patients, aswell as blood test apparatuses in the field of medicine.

1. A blood test apparatus that punctures skin using a laser to collectand measure blood, the apparatus comprising: a laser puncturing sectionthat emits a laser light to puncture the skin; a blood sensor thatcollects and analyzes the blood flowing out from the punctured skin; aholder that holds the blood sensor; a negative pressure section thatcreates a negative pressure in a space near the blood sensor; and anegative pressure controlling section that controls an operation of thenegative pressure section, wherein the negative pressure controllingsection changes a level of the negative pressure in the space near theblood sensor using a predetermined pattern, in at least part of a periodfrom when the skin abuts on the holder until when the measurement iscomplete.
 2. The blood test apparatus according to claim 1, wherein thenegative pressure controlling section controls the operation of thenegative pressure section such that the level of the negative pressurein the space near the blood sensor changes within a predetermined rangeand in a predetermined cycle, in at least part of the period from whenthe skin abuts on the holder until when the measurement is complete. 3.The blood test apparatus according to claim 1, wherein the negativepressure controlling section changes the level of the negative pressurein the space near the blood sensor using the predetermined pattern, in aperiod from when the skin abuts on the holder until when bloodcollection is detected by the blood sensor.
 4. The blood test apparatusaccording to claim 1, wherein: the negative pressure section comprises anegative pressure pump and a negative pressure valve; and the negativepressure controlling section controls opening and closing of thenegative pressure valve to change the level of the negative pressure inthe space near the blood sensor using the predetermined pattern.
 5. Theblood test apparatus according to claim 1, wherein the negative pressurecontrolling section releases the negative pressure in the space near theblood sensor when blood collection is detected by the blood sensor, andthen stops the operation of the negative pressure section whenmeasurement of the collected blood is completed.
 6. The blood testapparatus according to claim 1, further comprising a first skin contactsensor that detects that the skin abuts on the holder, wherein thenegative pressure controlling section makes the negative pressuresection start creating a negative pressure based on output of the firstskin contact sensor.
 7. The blood test apparatus according to claim 1,wherein the negative pressure controlling section detects a signal thatdrives the negative pressure section and detects a defect or environmentof the negative pressure section based on the detected signal.
 8. Theblood test apparatus according to claim 1, where in the negativepressure controlling section changes the level of the negative pressurein the space near the blood sensor using the predetermined pattern,after the skin is punctured by the laser puncturing section.
 9. Theblood test apparatus according to claim 1, wherein the negative pressurecontrolling section controls the operation of the negative pressuresection such that the level of the negative pressure in the space nearthe blood sensor becomes higher after the skin is punctured than beforethe skin is punctured.
 10. The blood test apparatus according to claim1, wherein: the blood sensor forms a blood sensor unit in an integratedmanner with the holder; the blood sensor unit is formed with a chassis,both ends of which open such that one end is attached to an apparatusbody and the other end abuts on the skin, and the blood sensor that isprovided such that a space of an interior of the chassis is separatedinto a space closer to the apparatus body and a space closer to theskin; and the negative pressure section creates the negative pressure inthe space closer to the skin from the space closer to the apparatus bodyvia a hole provided in the blood sensor.
 11. The blood test apparatusaccording to claim 10, wherein a hole that communicates between thespace closer to the apparatus body and the space closer to the skin isprovided in the blood sensor unit.
 12. The blood test apparatusaccording to claim 10, wherein: the blood sensor comprises: a storingpart which opens downward and stores the blood flowing out from thepunctured skin; a supply channel, one end of which is connected to thestoring part; a detecting section which is provided on the supplychannel; and an air hole which is provided in the other end of thesupply channel and opens upward to communicate with an outer space; andthe negative pressure section creates the negative pressure on the skinvia the air hole, the supply channel and the storing part.
 13. The bloodtest apparatus according to claim 12, wherein the negative pressurecontrolling section stops the operation of the negative pressure sectionwhen it is detected that the blood has reached the detecting section.14. The blood test apparatus according to claim 12, wherein: a secondskin contact sensor that detects that the skin is abutted, is providedin the blood sensor or an attaching part attached to the blood sensor;and the negative pressure controlling section makes the negativepressure section stop creating the negative pressure based on output ofthe second skin contact sensor.
 15. The blood test apparatus accordingto claim 10, wherein an attaching part to which the blood sensor isattached, is provided in the blood sensor unit, and a negative pressurepath is provided in the attaching part.
 16. The blood test apparatusaccording to claim 10, wherein the negative pressure controlling sectionstops the operation of the negative pressure section when measurement ofthe collected blood is complete.
 17. A blood test apparatus thatpunctures skin using a laser and collects and measures blood, theapparatus comprising: a laser puncturing section that emits a laserlight to puncture the skin; a blood sensor that collects and analyzesthe blood flowing out from the punctured skin; a holder that holds theblood sensor; and a negative pressure section that creates a negativepressure in a space near the blood sensor, wherein the negative pressuresection drives a manual pump to create the negative pressure.
 18. Theblood test apparatus according to claim 17, wherein the manual pumpconstituting the negative pressure section is driven by moving a manualpump knob up and down with respect to the manual pump.
 19. The bloodtest apparatus according to claim 18, wherein the manual pump knob hasindentations and projections.
 20. A controlling method for a blood testapparatus that comprises: a laser puncturing section that emits a laserlight to puncture skin; a blood sensor that collects and analyzes bloodflowing out from the punctured skin; a holder that holds the bloodsensor; a negative pressure section that creates a negative pressure ina space near the blood sensor; and a negative pressure controllingsection that controls an operation of the negative pressure section,wherein, in at least part of a period from when the skin abuts on theholder until when measurement is completed, a level of the negativepressure in the space near the blood sensor is changed using apredetermined pattern.
 21. The controlling method for the blood testapparatus according to claim 20, wherein the operation of the negativepressure section is controlled such that, in at least part of the periodfrom when the holder abuts on the skin until when the measurement iscomplete, the level of the negative pressure in the space near the bloodsensor is changed within a predetermined range and in a predeterminedcycle.
 22. The controlling method of the blood test apparatus accordingto claim 20, wherein, in a period from when the skin abuts on the holderuntil when the blood sensor detects blood collection, the level of thenegative pressure in the space near the blood sensor is changed using apredetermined pattern.
 23. The controlling method for the blood testapparatus according to claim 20, wherein: the negative pressure sectioncomprises a negative pressure pump and a negative pressure valve; andthe level of the negative pressure in the space near the blood sensor ischanged using the predetermined pattern by controlling opening andclosing of the negative pressure valve.